An ion-imprinted polymer material and its applications

Abstract

This invention relates to the field of adsorption and separation technology, specifically to an ion-imprinted polymer material and its applications. The ion-imprinted polymer is prepared according to the following steps: 4-acetoxystyrene or a mixture of 4-acetoxystyrene and other olefin monomers are polymerized under the action of an initiator to obtain a polymer; hydrazine hydrate is added to the polymer solution for hydrolysis to obtain a polymer containing phenolic hydroxyl groups; after dissolving the phenolic hydroxyl-containing polymer, template ions are added for spontaneous coordination; the resulting coordination product undergoes a crosslinking reaction with formaldehyde to obtain the ion-imprinted polymer material. The ion-imprinted polymer material prepared by this invention exhibits strong selective recognition and adsorption capabilities, as well as a high selective adsorption capacity.

Description

Technical Field

[0001] This invention relates to the field of adsorption and separation technology, specifically to an ion-imprinted polymer material and its applications. Background Technology

[0002] Rare and precious metal elements are mainly used in high-tech fields. For example, they are essential materials for infrared technology such as rubidium atomic clocks and radiation detection equipment, and are also important materials for photoelectric conversion such as photovoltaic cells, photoelectric emitters, television camera tubes, and photomultiplier tubes. In addition, they have advantages in some traditional fields. For instance, cesium formate is the highest quality drilling and completion fluid for high-temperature, high-pressure oil and gas well drilling and completion operations, and it is irreplaceable in some high-tech industries. my country has abundant rubidium and cesium resources, mainly existing in the form of brine (ions), such as in the Qinghai Salt Lake, or distributed as solid ores in lepidolite and cesium garnet. Currently, methods for separating rubidium and cesium include stepwise crystallization, precipitation, solvent extraction, and ion exchange. For example, CN201710697750.2 discloses a method for extracting rubidium and cesium from salt lake brine. The method involves mixing t-BAMBP with a diluent to obtain an organic phase, then adding an alkaline solution and the organic phase for saponification. After separation, a saponified organic phase and an alkaline solution are obtained. The saponified organic phase is used to extract the salt lake brine, yielding an organic extract phase and an aqueous raffinate phase. The organic extract phase is then back-extracted to obtain a back-extracted phase containing Cs(I) and Rb(I) and a blank organic phase. Ion imprinting technology is a new technique that uses metal ions as templates, utilizing coordination bonds, covalent bonds, etc., to bind with functional monomers, and then cross-linking polymerizes them with initiators and cross-linking agents to prepare metal ion-specific adsorbent materials. For example, CN202211352709.9 discloses a graft polymerization method to prepare graphene oxide silica gel containing lithium ions. After polymerization, lithium ions are eluted to obtain a lithium ion imprinted polymer for lithium ion separation.

[0003] Currently, ion imprinting technology mainly uses liquid-liquid extraction as a method for extracting rubidium and cesium ions. The extractant is primarily substituted phenol, which utilizes the selective coordination of phenolic hydroxyl groups with rubidium and cesium ions to transfer them from the aqueous phase to the organic phase, thus achieving separation. However, liquid-liquid extraction requires the use of organic reagents and repeated extraction; furthermore, relying solely on the effect of phenolic hydroxyl groups for the adsorption and separation of rubidium and cesium ions is not very effective. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides an ion-imprinted polymer material that exhibits strong selective recognition and adsorption capabilities, as well as a high selective adsorption capacity, and requires no organic reagents during use.

[0005] To achieve the objective of this invention, the following technical solution is adopted:

[0006] The first objective of this invention is to provide an ion-imprinted polymer material, which is prepared according to the following steps:

[0007] 4-Acetoxystyrene or a mixture of 4-acetoxystyrene and other olefin monomers are polymerized under the action of an initiator to obtain a polymer;

[0008] Hydrazine hydrate was added to a solution of the polymer to carry out a hydrolysis reaction, yielding a polymer containing phenolic hydroxyl groups;

[0009] After dissolving the phenolic hydroxyl-containing polymer, template ions are added for spontaneous coordination. The resulting coordination product undergoes a cross-linking reaction with formaldehyde to obtain the ion-imprinted polymer material.

[0010] Preferably, the olefin monomer is selected from one or more of styrene, methyl methacrylate, ethyl methacrylate, acrylamide, or methacrylic acid acetate.

[0011] Preferably, the initiator is one of azobisisobutyronitrile, benzoyl peroxide, diisopropylbenzene peroxide, and phenylacetone oxide;

[0012] The polymerization reaction is carried out at 78–81°C.

[0013] Preferably, the molar ratio of the polymer to the hydrazine hydrate is 1:6 to 10;

[0014] The hydrolysis reaction was carried out at room temperature for 6–8 hours.

[0015] Preferably, the template ion is a rare or precious metal ion; the molar ratio of the polymer containing phenolic hydroxyl groups to the template ion is 2 to 4:1.

[0016] Preferably, the crosslinking reaction involves immersing the coordination product in a formaldehyde aqueous solution with pH > 7.5 for 1–24 h, and the formaldehyde aqueous solution contains a formaldehyde mass fraction of 10–37%.

[0017] Preferably, after the coordination product undergoes a cross-linking reaction with formaldehyde, the cross-linking reaction product is collected and soaked in a 0.1–1 mol / L HCl solution for 1–12 h to elute the template ions.

[0018] Preferably, the crosslinked product after template ion removal is processed and shaped to prepare ion-imprinted polymer materials in the form of nanofibers, porous microspheres, or porous membranes.

[0019] Preferably, the processing and forming method is electrospinning or phase inversion.

[0020] A second objective of this invention is to provide the use of the ion-imprinted polymer material in the separation and / or adsorption of rare and precious metal ions.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. This invention provides an ion-imprinted polymer material rich in multifunctional groups, obtained by crosslinking a polymer rich in phenolic hydroxyl groups with formaldehyde. During the synthesis of this polymer, 4-acetoxystyrene is copolymerized with other olefin monomers to obtain an intermediate polymer containing acetoxy groups and other functional groups (such as carboxyl, hydroxyl, ester, phenyl, and amino groups). Then, the acetoxy groups are hydrolyzed to generate phenolic hydroxyl groups, achieving a distribution and arrangement of phenolic hydroxyl groups and other functional groups on the polymer. This results in a highly efficient rare and precious metal ion-imprinted polymer material assisted by multifunctional groups, significantly improving the selectivity, adsorption capacity, and adsorption rate of rare and precious metal ions.

[0023] 2. The ion-imprinted polymer materials prepared based on phenolic hydroxyl polymers provided by this invention are in the form of porous materials, mainly porous microspheres, porous membranes or nanofibers, etc. These different forms of ion-imprinted polymer materials can be applied to different scenarios. For example, porous microspheres can be used for column chromatography separation, porous membranes can be used for adsorption separation in membrane filtration, and nanofibers can also be regarded as a kind of fiber membrane material.

[0024] 3. The ion-imprinted polymer material provided by this invention does not use organic reagents in the ion adsorption process, resulting in less environmental impact and lower cost. Attached Figure Description

[0025] Figure 1 The microstructure of the nanofiber membrane prepared in Example 1;

[0026] Figure 2 Microscopic morphology of the porous microspheres prepared in Example 2;

[0027] Figure 3 Electron micrograph of the porous membrane material prepared in Example 11. Detailed Implementation

[0028] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0029] Example 1

[0030] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0031] 0.1 g of AIBN was dissolved in 20 g of acetoxystyrene to form an initiator-monomer system. This solution was then slowly added to a 0.1% (w / w) polyvinyl alcohol (stabilizer) solution while stirring and heating to 80°C for 4 hours to obtain bead-like polymers. The mixture was filtered, and the solids were collected. The resulting solids were dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0032] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the polymer containing phenolic hydroxyl groups.

[0033] A viscous spinning solution containing phenolic hydroxyl groups was dissolved in methanol to obtain a 30 wt% solids content. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 12 kV, feed rate 0.02 ml / h, receiving distance 5 cm, ambient temperature 20℃, ambient humidity 40%, and spinning time 1 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (pH 8.5) formaldehyde aqueous solution for 2 h. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 h to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. Its microstructure is shown in [Figure 1]. Figure 1 The adsorption capacity for rubidium ions was determined to be 150 mg / g, Rb + / K + The selectivity coefficient is 125.

[0034] Example 2

[0035] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0036] 0.1 g of AIBN was dissolved in a mixed solution of acetoxystyrene and styrene to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene to styrene was 50:1. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol by mass, while stirring and heating to 80°C for 4 hours to obtain bead-like polymers. The bead-like polymers were collected by vacuum filtration. The resulting solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0037] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0038] A phenolic hydroxyl polymer was dissolved in tetrahydrofuran to obtain a viscous liquid with a solid content of 30%. 0.02 g of RbCl was added to the viscous liquid, and after complete dissolution, it was added dropwise to deionized water using a capillary dropper. Solvent-nonsolvent exchange occurred in the deionized water, followed by curing to prepare porous microspheres. The diameter of the microspheres could be controlled using capillary droppers of different diameters, ranging from 500 nm to 1.2 mm. The cured porous microspheres were then immersed in an alkaline 17% formaldehyde aqueous solution for 2 hours for crosslinking. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 12 hours to elute template ions, thus preparing rubidium-cesium ion-imprinted porous membrane microspheres. The microstructure is shown in [Figure showing microstructure]. Figure 2 The adsorption capacity for rubidium ions was determined to be 230 mg / g, Rb + / K + The selectivity coefficient is 125.

[0039] Example 3

[0040] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0041] 0.1 g of AIBN was dissolved in a mixed solution of acetoxystyrene and methyl methacrylate to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene to methyl methacrylate was 20:1. This solution was slowly added to an aqueous solution containing 0.1% polyvinyl alcohol (stabilizer) by mass, while stirring and heating to 80°C for 4 hours to obtain bead-like polymers. The mixture was filtered, and the solids were collected. The obtained solids were dissolved in tetrahydrofuran, precipitated in methanol, and the precipitated product was filtered and dried to obtain the polymer.

[0042] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate (molar ratio of polymer to hydrazine hydrate was 1:6) was added. The mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution. The precipitate was dried at 80°C to obtain the hydrolyzed product, which is the polymer containing phenolic hydroxyl groups. During hydrolysis, the acetoxy group was removed to form phenolic hydroxyl groups, and the methyl ester group was removed to form carboxyl groups.

[0043] A viscous spinning solution containing phenolic hydroxyl groups was dissolved in methanol to obtain a 30 wt% solids content. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 12 kV, feed rate 0.02 ml / h, receiving distance 5 cm, ambient temperature 20℃, ambient humidity 40%, and spinning time 1 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (pH 8.5) formaldehyde aqueous solution for 2 h. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 4 h to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. The adsorption capacity for rubidium ions was determined to be 160 mg / g, Rb... + / K + The selectivity coefficient is 355.

[0044] Example 4

[0045] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0046] 0.1 g of AIBN was dissolved in a mixed solution of acetoxystyrene and ethyl methacrylate to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene to ethyl methacrylate was 20:1. This solution was slowly added to an aqueous solution containing 0.1% polyvinyl alcohol (stabilizer) by mass, while stirring and heating to 80°C for 4 hours to obtain bead-like polymers. The mixture was filtered, and the solids were collected. The obtained solids were dissolved in tetrahydrofuran, precipitated in methanol, and the precipitated product was filtered and dried to obtain the polymer.

[0047] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate (molar ratio of polymer to hydrazine hydrate was 1:6) was added. The mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution. The precipitate was dried at 80°C to obtain the hydrolyzed product, which is the polymer containing phenolic hydroxyl groups. During hydrolysis, the acetoxy group was removed to form phenolic hydroxyl groups, and the ethyl ester group was removed to form carboxyl groups.

[0048] A viscous spinning solution containing phenolic hydroxyl groups was dissolved in methanol to obtain a 30 wt% solids content. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 12 kV, feed rate 0.02 ml / h, receiving distance 5 cm, ambient temperature 20℃, ambient humidity 40%, and spinning time 1 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (pH 8.5) formaldehyde aqueous solution for 2 h. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 h to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. The adsorption capacity for rubidium ions was determined to be 170 mg / g, and RbCl was also measured. + / K + The selectivity coefficient is 75.

[0049] Example 5

[0050] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0051] 0.1 g of AIBN was dissolved in a mixed solution of acetoxystyrene and acrylamide to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene to acrylamide was 30:1. This solution was slowly added to an aqueous solution containing 0.1% polyvinyl alcohol (stabilizer) by mass, while stirring and heating to 80°C for 4 hours to obtain bead-like polymer. The mixture was filtered, and the solid was collected. The obtained solid was dissolved in tetrahydrofuran, precipitated in methanol, and the precipitated product was filtered and dried to obtain the polymer.

[0052] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution. The precipitate was dried at 80°C to obtain the hydrolyzed product, which is the polymer containing phenolic hydroxyl groups. In this hydrolysis, the acetoxy group was removed to form phenolic hydroxyl groups, and acrylamide provided the amide groups.

[0053] A viscous spinning solution containing phenolic hydroxyl groups was dissolved in methanol to obtain a 30 wt% solids content. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 12 kV, feed rate 0.02 ml / h, receiving distance 5 cm, ambient temperature 20℃, ambient humidity 40%, and spinning time 1 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (pH 8.5) formaldehyde aqueous solution for 2 h. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 h to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. The adsorption capacity for rubidium ions was measured to be 152 mg / g, and RbCl was also measured. + / K + The selectivity coefficient is 85.

[0054] Example 6

[0055] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0056] 0.1 g of AIBN was dissolved in a mixed solution of acetoxystyrene and methacryl acetate to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene to methacryl acetate was 30:1. This solution was slowly added to an aqueous solution containing 0.1% polyvinyl alcohol (stabilizer) by mass, while stirring and heating to 80°C for 4 hours to obtain bead-like polymers. The mixture was filtered, and the solids were collected. The obtained solids were dissolved in tetrahydrofuran, precipitated in methanol, and the precipitated product was filtered and dried to obtain the polymer.

[0057] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate (molar ratio of polymer to hydrazine hydrate was 1:6) was added. The mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution. The precipitate was dried at 80°C to obtain the hydrolyzed product, which is the polymer containing phenolic hydroxyl groups. Specifically, after hydrolysis, the acetoxy group was removed to form the phenolic hydroxyl group, and the acetate group was removed to form the hydroxyl group.

[0058] A viscous spinning solution containing phenolic hydroxyl groups was dissolved in methanol to obtain a 30 wt% solids content. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 12 kV, feed rate 0.02 ml / h, receiving distance 5 cm, ambient temperature 20℃, ambient humidity 40%, and spinning time 1 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (pH 8.5) formaldehyde aqueous solution for 4 h. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 h to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. The adsorption capacity for rubidium ions was measured to be 255 mg / g, and RbCl was also measured. + / K + The selectivity coefficient is 325.

[0059] Example 7

[0060] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0061] 0.1 g of AIBN was dissolved in a mixed solution of acetoxystyrene and styrene to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene to styrene was 50:1. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol by mass, while stirring and heating to 80°C for 4 hours to obtain bead-like polymers. The bead-like polymers were collected by vacuum filtration. The resulting solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0062] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:10), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0063] A phenolic hydroxyl polymer was dissolved in tetrahydrofuran to obtain a viscous liquid with a solid content of 30%. 0.02 g of RbCl was added to the viscous liquid, and after complete dissolution, it was added dropwise to deionized water using a capillary dropper. Solvent-nonsolvent exchange occurred in the deionized water, followed by curing to prepare porous microspheres. The diameter of the microspheres could be controlled using capillary droppers of different diameters, ranging from 500 nm to 1.2 mm. The cured porous microspheres were then immersed in an alkaline 37% formaldehyde aqueous solution for 2 hours for crosslinking. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 hours to elute template ions, thus preparing rubidium-cesium ion-imprinted porous membrane microspheres. The adsorption capacity for rubidium ions was measured to be 550 mg / g, and RbCl was also measured to be 550 mg / g. + / K+ The selectivity coefficient is 325.

[0064] Example 8

[0065] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0066] 0.1 g of AIBN was dissolved in a mixed solution of acetoxystyrene and styrene to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene to styrene was 20:1. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol by mass, while stirring and heating to 80°C for 4 hours to obtain bead-like polymers. The bead-like polymers were collected by vacuum filtration. The resulting solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0067] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 8 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0068] A phenolic hydroxyl polymer was dissolved in tetrahydrofuran to obtain a viscous liquid with a solid content of 30%. 0.02 g of RbCl was added to the viscous liquid, and after complete dissolution, it was added dropwise to deionized water using a capillary dropper. Solvent-nonsolvent exchange occurred in the deionized water, and the mixture was then solidified to prepare porous microspheres. The diameter of the microspheres could be controlled using capillary droppers of different diameters, ranging from 500 nm to 1.2 mm. The solidified porous microspheres were then immersed in an alkaline, 37% formaldehyde aqueous solution for 2 hours for crosslinking. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 hours to elute template ions, thus preparing rubidium-cesium ion-imprinted porous membrane microspheres. The adsorption capacity for rubidium ions was measured to be 164 mg / g, and the RbCl adsorption capacity was [not specified in the original text]. + / K + The selectivity coefficient is 120.

[0069] Example 9

[0070] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0071] 0.1 g of AIBN was dissolved in a mixed solution of acetoxystyrene and styrene to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene to styrene was 50:1. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol by mass, while stirring and heating to 78°C for 4 hours to obtain bead-like polymers. The polymer was collected by vacuum filtration. The resulting solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0072] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0073] A phenolic hydroxyl polymer was dissolved in tetrahydrofuran to obtain a viscous liquid with a solid content of 30%. 0.02 g of CsCl was added to the viscous liquid, and after complete dissolution, it was added dropwise to deionized water using a capillary dropper. Solvent-nonsolvent exchange occurred in the deionized water, followed by curing to prepare porous microspheres. The diameter of the microspheres could be controlled using capillary droppers of different diameters, ranging from 500 nm to 1.2 mm. The cured porous microspheres were then immersed in an alkaline 37% formaldehyde aqueous solution for 2 hours for crosslinking. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 hours to elute template ions, thus preparing rubidium-cesium ion-imprinted porous membrane microspheres. The adsorption capacity for rubidium ions was measured to be 230 mg / g, and the CsCl adsorption capacity was [not specified]. + / K + The selectivity coefficient is 500, Cs + / Rb + The selectivity coefficient is 200.

[0074] Example 10

[0075] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0076] 0.1 g of AIBN was dissolved in a mixed solution of acetoxystyrene and styrene to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene to styrene was 20:1. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol by mass, while stirring and heating to 80°C for 6 hours to obtain bead-like polymers. The bead-like polymers were collected by vacuum filtration. The resulting solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0077] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0078] A phenolic hydroxyl polymer was dissolved in tetrahydrofuran to obtain a viscous liquid with a solid content of 30%. 0.02 g of RbCl was added to the viscous liquid and, after complete dissolution, it was added dropwise to deionized water using a capillary dropper. Solvent-nonsolvent exchange occurred in the deionized water, followed by curing to prepare porous microspheres. The diameter of the microspheres could be controlled using capillary droppers of different diameters, ranging from 500 nm to 1.2 mm. The cured porous microspheres were then immersed in an alkaline 37% formaldehyde aqueous solution for 2 hours for crosslinking. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 hours to elute template ions, thus preparing rubidium-cesium ion-imprinted porous membrane microspheres. The adsorption capacity for rubidium ions was measured to be 230 mg / g.

[0079] Example 11

[0080] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0081] 0.1 g of AIBN was dissolved in a mixed solution of acetoxystyrene and styrene to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene to styrene was 30:1. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol by mass, while stirring and heating to 80°C for 4 hours to obtain bead-like polymers. The polymer was collected by filtration. The resulting solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0082] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0083] A viscous liquid containing phenolic hydroxyl groups was dissolved in tetrahydrofuran to obtain a viscous solution with a solid content of 30%. 0.02 g of CsCl was added to the viscous liquid. The solution was then scraped into a liquid film using a spatula and solidified in a non-solvent coagulation bath to prepare a porous membrane material. Subsequently, the solidified porous membrane was immersed in an alkaline, 10% formaldehyde aqueous solution for 2 hours for crosslinking. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 hours to elute template ions, thus preparing a cesium ion-imprinted porous membrane. Its electron micrograph is shown below. Figure 3 The adsorption capacity for Cs ions was determined to be 90 mg / g. + / K + The selectivity coefficient is 300, Cs + / Rb + The selectivity coefficient is 140.

[0084] Example 12

[0085] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0086] 0.1 g of AIBN was dissolved in a mixed solution of acetoxystyrene and methyl methacrylate to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene to methyl methacrylate was 10:1. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol by mass, while stirring and heating to 80°C for 4 hours to obtain bead-like polymers. The polymer was collected by vacuum filtration. The resulting solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0087] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0088] A phenolic hydroxyl polymer was dissolved in tetrahydrofuran to obtain a viscous liquid with a solid content of 30%. 0.02 g of CsCl was added to the viscous liquid, and after complete dissolution, it was added dropwise to deionized water using a capillary dropper. Solvent-nonsolvent exchange occurred in the deionized water, and the mixture was then solidified to prepare porous microspheres. The diameter of the microspheres could be controlled using capillary droppers of different diameters, ranging from 500 nm to 1.2 mm. The solidified porous microspheres were then immersed in an alkaline 27% formaldehyde aqueous solution for 2 hours for crosslinking. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 hours to elute template ions, thus preparing cesium ion-imprinted porous membrane microspheres. The adsorption capacity for cesium ions was measured to be 260 mg / g, and CsCl was also measured to be 100 mg / g. + / K + The selectivity coefficient is 500, Cs + / Rb + The selectivity coefficient is 340.

[0089] Example 13

[0090] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0091] 0.1 g of AIBN was dissolved in 20 g of acetoxystyrene to form an initiator-monomer system. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol (stabilizer). The mixture was stirred and heated to 80°C for 4 hours to obtain bead-like polymers. The polymer was filtered, and the solid was collected. The solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0092] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the polymer containing phenolic hydroxyl groups.

[0093] A viscous spinning solution containing phenolic hydroxyl groups was dissolved in methanol to obtain a 30 wt% solids content. 0.02 g of RbCl was added to the spinning solution and dissolved completely before electrospinning. The electrospinning conditions were: voltage 25 kV, feed rate 1 ml / h, receiving distance 30 cm, ambient temperature 50℃, ambient humidity 70%, and spinning time 8 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (pH 8.5) formaldehyde aqueous solution for 2 h. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 h to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. The adsorption capacity for rubidium ions was measured to be 167 mg / g.

[0094] Example 14

[0095] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0096] 0.1 g of AIBN was dissolved in 20 g of acetoxystyrene to form an initiator-monomer system. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol (stabilizer). The mixture was stirred and heated to 80°C for 4 hours to obtain bead-like polymers. The polymer was filtered, and the solid was collected. The solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0097] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the polymer containing phenolic hydroxyl groups.

[0098] A viscous spinning solution containing phenolic hydroxyl groups was dissolved in methanol to obtain a 30 wt% solids content. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 18 kV, feed rate 0.08 ml / h, receiving distance 20 cm, ambient temperature 35℃, ambient humidity 60%, and spinning time 5 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (pH 8.5) formaldehyde aqueous solution for 2 h. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 h to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. The adsorption capacity for rubidium ions was measured to be 189 mg / g.

[0099] Example 15

[0100] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0101] 0.1 g of AIBN was dissolved in 20 g of acetoxystyrene to form an initiator-monomer system. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol (stabilizer). The mixture was stirred and heated to 80°C for 4 hours to obtain bead-like polymers. The polymer was filtered, and the solid was collected. The solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0102] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the polymer containing phenolic hydroxyl groups.

[0103] A viscous spinning solution containing phenolic hydroxyl groups was dissolved in methanol to obtain a 30 wt% solids content. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 18 kV, feed rate 0.08 ml / h, receiving distance 20 cm, ambient temperature 35℃, ambient humidity 60%, and spinning time 5 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (pH 8.5) formaldehyde aqueous solution for 20 h. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 h to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. The adsorption capacity for rubidium ions was measured to be 172 mg / g.

[0104] Example 16

[0105] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0106] 0.1 g of AIBN was dissolved in 20 g of acetoxystyrene to form an initiator-monomer system. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol (stabilizer). The mixture was stirred and heated to 80°C for 4 hours to obtain bead-like polymers. The polymer was filtered, and the solid was collected. The solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0107] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the polymer containing phenolic hydroxyl groups.

[0108] A viscous spinning solution containing phenolic hydroxyl groups was dissolved in methanol to obtain a 30 wt% solids content. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 18 kV, feed rate 0.08 ml / h, receiving distance 20 cm, ambient temperature 35℃, ambient humidity 60%, and spinning time 5 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (pH 8.5) formaldehyde aqueous solution for 12 h. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 h to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. The adsorption capacity for rubidium ions was measured to be 163 mg / g.

[0109] Example 17

[0110] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0111] 0.1 g of AIBN was dissolved in 20 g of acetoxystyrene to form an initiator-monomer system. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol (stabilizer). The mixture was stirred and heated to 80°C for 4 hours to obtain bead-like polymers. The polymer was filtered, and the solid was collected. The solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0112] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the polymer containing phenolic hydroxyl groups.

[0113] A viscous spinning solution containing phenolic hydroxyl groups was dissolved in methanol to obtain a 30 wt% solids content. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 20 kV, feed rate 0.08 ml / h, receiving distance 12 cm, ambient temperature 25℃, ambient humidity 60%, and spinning time 5 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (pH 8.5) formaldehyde aqueous solution for 24 h. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 h to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. The adsorption capacity for rubidium ions was measured to be 159 mg / g.

[0114] Example 18

[0115] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0116] 0.1 g of AIBN was dissolved in 20 g of acetoxystyrene to form an initiator-monomer system. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol (stabilizer). The mixture was stirred and heated to 80°C for 4 hours to obtain bead-like polymers. The polymer was filtered, and the solid was collected. The solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0117] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the polymer containing phenolic hydroxyl groups.

[0118] A viscous spinning solution containing phenolic hydroxyl groups was dissolved in methanol to obtain a 30 wt% solids content. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 20 kV, feed rate 0.08 ml / h, receiving distance 12 cm, ambient temperature 25℃, ambient humidity 60%, and spinning time 5 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (pH 8.5) formaldehyde aqueous solution for 24 h. After crosslinking, the membrane was immersed in a 1 mol / L HCl solution for 12 h to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. The adsorption capacity for rubidium ions was measured to be 164 mg / g.

[0119] Example 19

[0120] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0121] 0.1 g of AIBN was dissolved in a mixed solution of acetoxystyrene and styrene to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene to styrene was 50:1. This solution was then slowly added to an aqueous solution containing 0.1% polyvinyl alcohol by mass, while stirring and heating to 81°C for 4 hours to obtain bead-like polymers. The bead-like polymers were collected by vacuum filtration. The resulting solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0122] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl, and dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0123] A phenolic hydroxyl polymer was dissolved in N,N-dimethylacetamide to obtain a viscous solution with a solid content of 20%. 0.02 g of RbCl was added to the spinning solution and dissolved completely. The homogeneous polymer solution was then poured onto a glass plate or nonwoven fabric substrate. A doctor blade with a certain gap was used to evenly spread the polymer solution onto the glass plate at a uniform speed. The substrate was then immersed in deionized water for curing. The cured porous membrane was then immersed in an alkaline 37% formaldehyde aqueous solution for crosslinking for 6 hours. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 hours to elute template ions, thus preparing the rubidium-cesium ion-imprinted porous membrane material. The adsorption capacity for rubidium ions was measured to be 180 mg / g.

[0124] Example 20

[0125] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0126] Benzoyl peroxide (BPO) was dissolved in a mixed solution of styrene, styrene, and methyl methacrylate to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene, styrene, and methyl methacrylate was 10:2:1. This initiator-monomer system solution was slowly added to a 0.1% (w / w) polyvinyl alcohol solution while stirring and heating to 80°C to obtain bead-like polymers. The mixture was filtered, and the solid was collected. The resulting solid was dissolved in tetrahydrofuran, precipitated in methanol, and the precipitated product was filtered and dried to obtain the polymer.

[0127] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl, and dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0128] A phenolic hydroxyl polymer was dissolved in N,N-dimethylformamide to obtain a viscous solution with a solid content of 10%. 0.02 g of RbCl was added to the viscous solution and, after complete dissolution, the homogeneous polymer solution was added dropwise to deionized water using a capillary dropper. Solvent-nonsolvent exchange occurred in the deionized water, followed by curing to prepare porous microspheres. The diameter of the microspheres was controllable, ranging from 500 nm to 1.2 mm. The cured porous microspheres were then immersed in an alkaline 37% formaldehyde aqueous solution for crosslinking for 2 hours. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for at least 2 hours to elute template ions, thus preparing rubidium ion-imprinted porous membrane microspheres. The adsorption capacity for rubidium ions was determined to be 520 mg / g.

[0129] Example 21

[0130] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0131] Benzoyl peroxide (BPO) was dissolved in a mixed solution of styrene, styrene, and methyl methacrylate to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene, styrene, and methyl methacrylate was 6:1:2. This initiator-monomer system solution was slowly added to a 0.1% (w / w) polyvinyl alcohol solution while stirring and heating to 80°C to obtain bead-like polymers. The mixture was filtered, and the solid was collected. The obtained solid was dissolved in tetrahydrofuran, precipitated in methanol, and the precipitated product was filtered and dried to obtain the polymer.

[0132] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl, and dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0133] A phenolic hydroxyl polymer was dissolved in N,N-dimethylformamide to obtain a viscous solution with a solid content of 20%. 0.02 g of RbCl was added to the viscous solution and, after complete dissolution, the homogeneous polymer solution was added dropwise to deionized water using a capillary dropper. Solvent-nonsolvent exchange occurred in the deionized water, followed by curing to prepare porous microspheres. The diameter of the microspheres was controllable, ranging from 500 nm to 1.2 mm. The cured porous microspheres were then immersed in an alkaline 37% formaldehyde aqueous solution for crosslinking for 2 hours. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for at least 2 hours to elute template ions, thus preparing rubidium ion-imprinted porous membrane microspheres. The adsorption capacity for rubidium ions was determined to be 520 mg / g.

[0134] Example 22

[0135] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0136] Benzoyl peroxide (BPO) was dissolved in a mixture of acetoxystyrene, styrene, and ethyl methacrylate to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene, styrene, and ethyl methacrylate was 4:1:1. The initiator-monomer system solution was slowly added to an aqueous solution containing 0.1% polyvinyl alcohol by mass, while stirring and heating to 80°C to obtain bead-like polymers. The mixture was filtered, and the solid was collected. The obtained solid was dissolved in tetrahydrofuran, precipitated in methanol, and the precipitated product was filtered and dried to obtain the polymer.

[0137] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl, and dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0138] A viscous spinning solution with a solid content of 10% was prepared by dissolving a phenolic hydroxyl polymer in N,N-dimethylformamide. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, the homogeneous polymer solution was added dropwise to deionized water using a capillary dropper. Solvent-nonsolvent exchange occurred in the deionized water, followed by curing to prepare porous microspheres. The diameter of these microspheres was adjustable, ranging from 500 nm to 1.2 mm. The cured porous microspheres were then immersed in an alkaline 17% formaldehyde aqueous solution for crosslinking for 6 hours. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 hours to elute template ions, thus preparing rubidium ion-imprinted porous membrane microspheres. The adsorption capacity for rubidium ions was measured to be 450 mg / g.

[0139] Example 23

[0140] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0141] Benzoyl peroxide (BPO) was dissolved in a mixture of acetoxystyrene, styrene, and methacrylic acid acetate to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene, styrene, and methacrylic acid acetate was 20:1:5. The initiator-monomer system solution was slowly added to an aqueous solution containing 0.1% polyvinyl alcohol by mass, while stirring and heating to 80°C to obtain bead-like polymers. The polymer was collected by vacuum filtration. The obtained solid was dissolved in tetrahydrofuran, precipitated in methanol, and the precipitated product was filtered and dried to obtain the polymer.

[0142] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl, and dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0143] A viscous spinning solution with a solid content of 10-20% was obtained by dissolving a phenolic hydroxyl polymer in N-methylpyrrolidone. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 12 kV, feed rate 0.02 ml / h, receiving distance 5 cm, ambient temperature 20℃, ambient humidity 40%, and spinning time 1 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (v / v) formaldehyde aqueous solution (pH 8.5) for 2 h. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 3 h to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. The adsorption capacity for rubidium ions was measured to be 520 mg / g.

[0144] Example 24

[0145] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0146] Dicumyl peroxide (IPBP) was dissolved in a mixture of acetoxystyrene, styrene, methacrylic acid, and ethyl methacrylate to form an initiator-monomer system, wherein the molar ratio of acetoxystyrene, styrene, methacrylic acid, and ethyl methacrylate was 20:1:5:5. The initiator-monomer system solution was slowly added to an aqueous solution containing 0.1% polyvinyl alcohol by mass, while stirring and heating to 80°C to obtain bead-like polymers. The polymer was collected by vacuum filtration. The obtained solid was dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0147] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl, and dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0148] A phenolic hydroxyl polymer was dissolved in N-methylpyrrolidone to obtain a viscous solution with a solid content of 10-40%. 0.02 g of RbCl was added to the viscous solution and, after complete dissolution, the homogeneous polymer solution was added dropwise to deionized water using a capillary dropper. Solvent-nonsolvent exchange occurred in the deionized water, followed by curing to prepare porous microspheres. The diameter of these microspheres was adjustable, ranging from 500 nm to 1.2 mm. The cured porous microspheres were then immersed in a 37% formaldehyde aqueous solution (pH 8.5) for 2 hours for crosslinking. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for 2 hours to elute template ions, thus preparing rubidium ion-imprinted porous membrane microspheres. The adsorption capacity for rubidium ions was determined to be 650 mg / g.

[0149] Example 25

[0150] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method: Phenylacetone oxide (BzAIBN) was dissolved in a mixture of acetoxystyrene, styrene, methacrylic acid acetate, ethyl methacrylate, and acrylamide to form an initiator-monomer system, denoted as solution 2. The molar ratio of acetoxystyrene, styrene, methacrylic acid acetate, ethyl methacrylate, and acrylamide was 1:1:1:1:1:0.2:1.2:0.8:1.8. The initiator-monomer system solution was slowly added to an aqueous solution containing 0.1% polyvinyl alcohol by mass, while stirring and heating to 80°C to obtain bead-like polymers. The mixture was filtered, and the solid was collected. The obtained solid was dissolved in tetrahydrofuran, precipitated in methanol, and the precipitated product was filtered and dried to obtain the polymer.

[0151] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl, and dried at 80°C to obtain the hydrolyzed product, which is the phenolic hydroxyl-containing polymer.

[0152] A viscous spinning solution with a solid content of 10% was obtained by dissolving a phenolic hydroxyl polymer in a mixed solvent of N,N-dimethylformamide and chloroform (volume ratio 1:1). 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 12 kV, feed rate 0.02 ml / h, receiving distance 5 cm, ambient temperature 20℃, ambient humidity 40%, and spinning time 1 h, yielding a nanofiber membrane. This nanofiber membrane was then immersed in a 37% (v / v) formaldehyde aqueous solution (pH 8.5) for 2 h. After crosslinking, the membrane was immersed in a 0.1 mol / L HCl solution for at least 2 hours to elute template ions, thus preparing the rubidium ion-imprinted nanofiber membrane material. The adsorption capacity for rubidium ions was determined to be 800 mg / g.

[0153] Comparative Example

[0154] An ion-imprinted polymer based on a phenolic hydroxyl-containing polymer was prepared by the following method:

[0155] 0.1 g of AIBN was dissolved in 20 g of acetoxystyrene to form an initiator-monomer system. This solution was then slowly added to a 0.1% (w / w) polyvinyl alcohol (stabilizer) solution while stirring and heating to 80°C for 4 hours to obtain bead-like polymers. The mixture was filtered, and the solids were collected. The resulting solids were dissolved in tetrahydrofuran and precipitated in methanol. The precipitated product was filtered and dried to obtain the polymer.

[0156] The polymer obtained above was dissolved in tetrahydrofuran, and hydrazine hydrate was added (the molar ratio of polymer to hydrazine hydrate was 1:6), and the mixture was stirred for 6 hours. After the reaction was completed, the product was precipitated in 1M HCl solution, and the precipitate was dried at 80°C to obtain the hydrolyzed product, which is the polymer containing phenolic hydroxyl groups.

[0157] A viscous spinning solution containing phenolic hydroxyl groups was dissolved in methanol to obtain a 30 wt% solids content. 0.02 g of RbCl was added to the spinning solution and, after complete dissolution, electrospinning was performed. The electrospinning conditions were: voltage 12 kV, feed rate 0.02 ml / h, receiving distance 5 cm, ambient temperature 20℃, ambient humidity 40%, and spinning time 1 h, yielding a nanofiber membrane. The adsorption capacity for rubidium ions was determined to be 30 mg / g, and Rb... + / K + The selectivity coefficient is 15.

[0158] The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. Therefore, although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention; and all technical solutions and improvements that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. An ion-imprinted polymer material, characterized in that, It is prepared according to the following steps: 4-Acetoxystyrene or a mixture of 4-acetoxystyrene and other olefin monomers are polymerized under the action of an initiator to obtain a polymer; Hydrazine hydrate was added to a solution of the polymer to carry out a hydrolysis reaction, yielding a polymer containing phenolic hydroxyl groups; After dissolving the phenolic hydroxyl-containing polymer, template ions are added for spontaneous coordination. The resulting coordination product is processed and shaped, and then cross-linked with formaldehyde. The cross-linking reaction product is collected and soaked in 0.1~1 mol / L HCl solution for 1~12h to elute the template ions, thus obtaining the ion-imprinted polymer material. The crosslinking reaction involves immersing the coordination product in a formaldehyde aqueous solution with pH > 7.5 for 1 to 24 hours, wherein the formaldehyde aqueous solution contains a formaldehyde mass fraction of 10 to 37%.

2. The ion-imprinted polymer material according to claim 1, characterized in that, The olefin monomer is selected from one or more of styrene, methyl methacrylate, ethyl methacrylate, acrylamide, or methacrylic acid acetate.

3. The ion-imprinted polymer material according to claim 1, characterized in that, The initiator is one of azobisisobutyronitrile, benzoyl peroxide, and dicumyl peroxide; The polymerization reaction is carried out at 78~81℃.

4. The ion-imprinted polymer material according to claim 1, characterized in that, The molar ratio of the polymer to the hydrazine hydrate is 1:6~10; The hydrolysis reaction was carried out at room temperature for 6-8 hours.

5. The ion-imprinted polymer material according to claim 1, characterized in that, The template ion is a rubidium ion or a cesium ion; the molar ratio of the polymer containing phenolic hydroxyl groups to the template ion is 2~4:

1.

6. The ion-imprinted polymer material according to claim 5, characterized in that, The ion-imprinted polymer material is an ion-imprinted polymer material in the form of nanofibers, porous microspheres, or porous membranes.

7. The ion-imprinted polymer material according to claim 1, characterized in that, The processing and forming method is electrospinning or phase inversion.

8. Use of the ion-imprinted polymer material according to any one of claims 1 to 7 in the separation and / or adsorption of rubidium ions or cesium ions.

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