A borate ion surface imprinted fiber, preparation method thereof and application thereof

Abstract

The present invention discloses a borate ion surface-imprinted fiber, a preparation method thereof and an application thereof, belonging to the field of adsorption technology. The borate ion surface-imprinted fiber uses a polyolefin fiber as a matrix, grafts monomer A on the surface of the polyolefin fiber, and then the amino group of monomer B is connected with the epoxy group of monomer A through a ring-opening reaction for functional modification. The functionalized modified product is coordinated and loaded with borate ions, and then reacted with a cross-linking agent and the borate ions are washed away to obtain the borate ion surface-imprinted fiber. The monomer A is an ester compound containing an unsaturated acrylate group and an epoxy group; the monomer B is a molecule containing cis-ortho and meta-dihydroxy functional groups. The preparation conditions of the borate ion surface-imprinted fiber are mild, the process is simple and easy to operate, and no secondary pollution is generated during the preparation process, which is suitable for large-scale production.

Description

Technical Field

[0001] The present invention belongs to the technical field of adsorption, and particularly relates to a borate ion surface imprinted fiber, a preparation method thereof and an application thereof. Background Art

[0002] Boron is indispensable in industries such as glass, ceramics, metallurgy, agriculture, medicine, semiconductors, and nuclear industry. China is a large country in industrial boron use. However, due to limitations in reserves and production capacity, a large amount of boron needs to be imported every year.

[0003] Ore and salt lake brine boron resources are abundant. However, the operation of extracting boron from ore is cumbersome and requires steps such as crushing, flotation, acidification, and separation. This not only consumes a large amount of chemical reagents but also causes environmental pollution. China's salt lake brine boron resources are abundant, accounting for about 40% of the boron reserves. Strengthening the effective development and utilization of boron resources in salt lake brines can not only reduce the development difficulty and meet market demand but also contribute to the comprehensive utilization of salt lake brine resources. The main methods for boron extraction in industry include acidification crystallization method, precipitation method, solvent extraction method, adsorption method, and membrane separation method, etc. Among them, the acidification crystallization method is the mainstream boron extraction process. However, due to the low recovery rate, it needs to be combined with other methods to improve the efficiency of boron extraction from salt lake brines. At the same time, the World Health Organization stipulates that the boron mass concentration in drinking water and irrigation water should not exceed 0.5 mg / L and 1.0 mg / L respectively, while the boron concentration in industrial boron extraction wastewater usually exceeds this standard. If it is not purified and treated, it will cause pollution of drinking water and irrigation water. Therefore, further purification and treatment are required.

[0004] The adsorption method for boron extraction uses an adsorbent to enrich boron from brine, and then an eluent is used to elute boron from the resin to obtain boric acid products. The adsorption method has the advantages of high adsorption efficiency, renewable utilization, and good enrichment effect, and has been studied more in boron adsorption, especially in the adsorption of low-concentration boric acid. Adsorbents mainly include two categories: inorganic adsorbents and organic adsorbents. Common inorganic adsorbents include metal hydroxides, activated carbon, cellulose derivatives, metal oxides, etc., and organic adsorbents are mainly ion exchange resins. However, the existing adsorbents have deficiencies in aspects such as adsorption capacity, adsorption rate, and adsorption selectivity. At the same time, the regeneration process of granular resin adsorbents is relatively long and the adsorption capacity loss is large. There is an urgent need to develop new adsorption materials. Summary of the Invention

[0005] The adsorbents for boron adsorption in the prior art have deficiencies in aspects such as adsorption capacity, adsorption rate, and adsorption selectivity. To solve this technical problem, the present invention provides a borate ion surface imprinted fiber, a preparation method thereof and an application thereof, which can selectively adsorb and separate borate ions in boron-containing wastewater in the presence of competitive ions.

[0006] To achieve the above object, the technical solution provided by the present invention is:

[0007] The present invention provides a borate ion surface-imprinted fiber. Using a polyolefin fiber as a matrix, monomer A is grafted onto the surface of the polyolefin fiber, and then the amino group of monomer B is connected through a ring-opening reaction with the epoxy group of monomer A for functional modification. The functionalized modified product is coordinated to load borate ions, and then after reacting with a crosslinking agent, the borate ions are washed away to obtain the borate ion surface-imprinted fiber.

[0008] The polyolefin fiber and monomer A generate a large number of highly active substances such as hydroxyl radicals and peroxide radicals through plasma discharge to ionize and dissociate monomer A. An addition reaction occurs between these active substances and monomer A to form a polymer connection on the matrix surface. The functionalized modified product coordinated to load borate ions reacts with the crosslinking agent. Through the double bond addition reaction between the product and the crosslinking agent, chemical bonds are generated between molecules and linear molecules are interconnected to form a three-dimensional network structure.

[0009] The polyolefin fiber is an isotactic polymer with high crystallinity. Its average molecular weight is 180,000 - 300,000, the polydispersity coefficient of the general molecular weight distribution is 4 - 7, the melt index is 1100 - 2100 g / min, and the polyolefin regularity > 95%. Further, the polyolefin fiber is selected from one of polypropylene fiber, polyethylene fiber, polyvinyl chloride fiber, polystyrene fiber, etc.

[0010] Monomer A is an ester compound containing an unsaturated acrylate group and an epoxy group; further, monomer A is glycidyl methacrylate (GMA).

[0011] Monomer B is a molecule containing cis - ortho and meta - dihydroxy functional groups. Further, monomer B is selected from one of glucosamine (GLU), N - methyl - D - glucamine (NMDG), saccharides, nucleosides (NUC), catecholamines (CA), polysaccharides, glycoproteins (GP), and glycopeptides.

[0012] The crosslinking agent is selected from one of dopamine, aniline, epichlorohydrin, N,N - dimethylformamide, and glutaraldehyde.

[0013] The mass ratio of the polyolefin fiber, monomer A, monomer B, and crosslinking agent is: 1:50 - 200:40 - 150:50 - 550.

[0014] The present invention also provides a method for preparing borate ion surface imprinted fibers. Using polyolefin fibers as the substrate, monomer A is polymerized onto the surface of polyolefin fibers by means of low-temperature radio frequency discharge plasma polymerization to obtain modified polyolefin fibers; monomer B is subjected to a ring-opening reaction with the epoxy groups on the modified polyolefin fibers to obtain functionalized polyolefin fibers; the functionalized polyolefin fibers are coordinated and loaded with borate ions, and then cross-linked with a cross-linking agent, and the borate ions are washed away to obtain borate ion surface imprinted fibers.

[0015] The method for preparing the borate ion surface imprinted fibers specifically includes the following steps:

[0016] (1) Immerse the polyolefin fibers fully in the monomer A modification solution. After drying the immersed polyolefin fibers, place them in a low-temperature plasma device and irradiate back and forth in a monomer atmosphere to enable the polyolefin fibers to fully undergo plasma polymerization reaction with monomer A. After the reaction ends, place the polyolefin fibers in the monomer A modification solution again and react at 60 - 80 °C for 1 - 3 h to obtain modified polyolefin fibers;

[0017] (2) Dissolve monomer B in a solvent, then add the modified polyolefin fibers in step (1), and react at 60 - 80 °C for 6 - 10 h. After the reaction ends, wash and dry to obtain functionalized polyolefin fibers;

[0018] (3) Place the functionalized polyolefin fibers in step (2) in a borate solution. After the functionalized polyolefin fibers are fully coordinated and loaded with borate ions, add a cross-linking agent to the solution and carry out cross-linking at a temperature of 50 - 70 °C for 2 - 6 h; after the cross-linking reaction ends, elute and remove the borate ions with an alkaline solution to obtain borate ion surface imprinted fibers.

[0019] The composition of the monomer A modification solution in step (1) is monomer A, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4, where the mass ratio of ammonium iron(II) sulfate hexahydrate, GMA, water, ethanol, and H2SO4 is 1:10 - 30:10 - 30:30 - 50:0.1 - 1.

[0020] The monomer atmosphere in step (1) is one of nitrogen, argon, helium, carbon dioxide, air, and oxygen.

[0021] The solvent in step (2) is one or a mixture of two of water, 1,4-dioxane, isopropanol, and dimethylformamide.

[0022] Another aspect of the present invention is to provide the application of the borate ion surface imprinted fiber as described above. Among them, the borate ion surface imprinted fiber is applied to adsorb and extract borate ions from boron-containing wastewater (such as salt lake brine and industrial wastewater). After the surface imprinted fiber is eluted and desorbed, it can be recycled five times, and its adsorption performance can still reach 85% of the initial adsorption amount.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) Using polyolefin fiber as the carrier, plasma polymerization surface modification is used to endow it with functional groups. Combining plasma polymerization modification and surface imprinting polymerization to prepare borate ion surface ion imprinted fiber. Utilizing the excellent physical and chemical properties of the matrix and integrating the advantages of the two technologies to develop a new type of adsorption material, which has the advantages of high adsorption capacity, long cycle service life, and highly selective adsorption of boron. It is especially suitable for adsorbing and extracting borate ions from boron-containing wastewater (salt lake brine and industrial wastewater), and enriches the theoretical system of the selective adsorption mechanism of oxyacid anions.

[0025] (2) The preparation conditions of the borate ion surface imprinted fiber are mild, the process is simple and easy to operate, and no secondary pollution is generated during the preparation process, which is suitable for large-scale production. Specific embodiments

[0026] In order to better understand the content of the present invention, the present invention will be further elaborated below in conjunction with embodiments. However, the content of the present invention is not limited to the following embodiments. Any equivalent changes or modifications made according to the core of the method of the present invention should be covered within the protection scope of the present invention. At the same time, on the premise of following the process parameter range described in the present invention application, the process parameters can be adjusted according to each embodiment and other qualified processes.

[0027] Example 1

[0028] Soak 0.1 g of PP in a 100 mL solution system containing GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 solution for 24 h. The mass ratio of GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 is 20:15:40:1:0.3. After the soaked PP fibers are air-dried, place them in a low-temperature plasma device and irradiate them back and forth for 180 s in a high-purity argon atmosphere. After plasma polymerization is completed, quickly put the fibers into 15 mL of GMA solution and heat them in a 70 °C water bath for 1 h to obtain modified polyolefin fiber PP-g-GMA. Dissolve 12 g of GLU in 10 mL of pure water and 40 mL of an aqueous solution of 1,4-dioxane, and then add PP-g-GMA. Under mechanical stirring, heat the water bath to 70 °C and react for 8 h to obtain functionalized polyolefin fiber PP-g-GMA-GLU. Place the PP-g-GMA-GLU fibers in a 100 mg / L borate solution, fully oscillate them at room temperature for 2 h, and then place the PP-g-GMA-GLU fibers loaded with borate ions after sufficient coordination in an epichlorohydrin cross-linking agent solution and cross-link them at 60 °C for 4 h. After the cross-linking reaction is completed, elute and remove the borate ions with 0.1 mol / L NaOH solution to obtain borate ion surface-imprinted fiber I-(PP-g-GMA-GLU).

[0029] Example 2

[0030] Soak 0.1 g of PP in a 100 mL solution system containing GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 solution for 24 h. The mass ratio of GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 is 25:15:35:1:0.3. After the soaked PP fibers are air-dried, place them in a low-temperature plasma device and irradiate them back and forth for 180 s in a high-purity air atmosphere. After plasma polymerization is completed, quickly put the fibers into 15 mL of GMA solution and heat them in a 60 °C water bath for 2 h to obtain modified polyolefin fiber PP-g-GMA. Dissolve 10 g of NMDG in 10 mL of pure water and 40 mL of an aqueous solution of 1,4-dioxane, and then add PP-g-GMA. Under mechanical stirring, heat the water bath to 80 °C and react for 7 h to obtain functionalized polyolefin fiber PP-g-GMA-NMDG. Place the PP-g-GMA-NMDG fibers in a 100 mg / L borate solution, fully oscillate them at room temperature for 2 h, and then place the PP-g-GMA-NMDG fibers loaded with borate ions after sufficient coordination in a glutaraldehyde cross-linking agent solution and cross-link them at 60 °C for 3 h. After the cross-linking reaction is completed, elute and remove the borate ions with 0.1 mol / L NaOH solution to obtain borate ion surface-imprinted fiber I-(PP-g-GMA-NMDG).

[0031] Example 3

[0032] Soak 0.1 g of PP in a 100 mL solution system containing GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 solution for 24 h. The mass ratio of GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 is 15:15:35:1:0.45. After the soaked PP fibers are air-dried, place them in a low-temperature plasma device and irradiate them back and forth for 180 s in a high-purity argon atmosphere. After plasma polymerization is completed, quickly put the fibers into 5 mL of GMA solution and heat them in a water bath at 70 °C for 3 h to obtain modified polyolefin fiber PP-g-GMA. Dissolve 12 g of glucose in an aqueous solution of 12 mL of pure water and 38 mL of isopropanol, and then add PP-g-GMA. Under mechanical stirring, heat in a water bath to 70 °C and react for 8 h to obtain functionalized polyolefin fiber PP-g-GMA-GLU. Place the PP-g-GMA-GLU fibers in a 100 mg / L borate solution, shake them well at room temperature for 2 h, and then place the PP-g-GMA-GLU fibers loaded with borate ions after sufficient coordination in an epichlorohydrin cross-linking agent solution and cross-link at 60 °C for 5 h. After the cross-linking reaction is completed, elute and remove the borate ions with 0.1 mol / L NaOH solution to obtain borate ion surface imprinted fiber I-(PP-g-GMA-GLU).

[0033] Example 4

[0034] Soak 0.1 g of PVC in a 100 mL solution system containing GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 solution for 24 h. The mass ratio of GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 is 20:20:35:1:0.3. After the soaked PVC fibers are air-dried, place them in a low-temperature plasma device and irradiate them back and forth for 210 s in a high-purity argon atmosphere. After plasma polymerization is completed, quickly put the fibers into 10 mL of GMA solution and heat them in a water bath at 70 °C for 3 h to obtain modified polyolefin fiber PP-g-GMA. Dissolve 10 g of galactose in an aqueous solution of 20 mL of pure water and 30 mL of 1,4-dioxane, and then add PP-g-GMA. Under mechanical stirring, heat in a water bath to 60 °C and react for 8 h to obtain functionalized polyolefin fiber PP-g-GMA-GAL. Place the PP-g-GMA-GAL fibers in a 100 mg / L borate solution, shake them well at room temperature for 2 h, and then place the PP-g-GMA-GAL fibers loaded with borate ions after sufficient coordination in an epichlorohydrin cross-linking agent solution and cross-link at 70 °C for 5 h. After the cross-linking reaction is completed, elute and remove the borate ions with 0.1 mol / L NaOH solution to obtain borate ion surface imprinted fiber I-(PP-g-GMA-GAL).

[0035] Example 5

[0036] Soak 0.1 g of PVC in a 100 mL solution system containing GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 for 24 h. The mass ratio of GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 is 25:10:35:1:0.36. After the soaked PP fibers are air-dried, put them into a low-temperature plasma device and irradiate them back and forth for 210 s in a high-purity nitrogen atmosphere. After plasma polymerization is completed, quickly put the fibers into 10 mL of GMA solution and heat them in a 60 °C water bath for 2 h to obtain modified polyolefin fiber PP-g-GMA. Dissolve 15 g of NMDG in an aqueous solution of 15 mL of pure water and 35 mL of dimethylformamide, and then add PP-g-GMA. Under mechanical stirring, heat the water bath to 80 °C and react for 7 h to obtain functionalized polyolefin fiber PP-g-GMA-NMDG. Place the PP-g-GMA-NMDG fiber in a 100 mg / L borate solution, fully oscillate it at room temperature for 2 h, and then place the PP-g-GMA-NMDG fiber loaded with borate ions after full coordination in a glutaraldehyde cross-linking agent solution and cross-link it at 80 °C for 4 h. After the cross-linking reaction is completed, elute and remove the borate ions with 0.1 mol / L NaOH solution to obtain borate ion surface-imprinted fiber I-(PP-g-GMA-NMDG).

[0037] Example 6

[0038] Soak 0.1 g of PE in a 100 mL solution system containing GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 for 24 h. The mass ratio of GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 is 20:20:31:1:0.36. After the soaked PP fibers are air-dried, put them into a low-temperature plasma device and irradiate them back and forth for 150 s in a high-purity oxygen atmosphere. After plasma polymerization is completed, quickly put the fibers into 20 mL of GMA solution and heat them in a 60 °C water bath for 1 h to obtain modified polyolefin fiber PP-g-GMA. Dissolve 10 g of GLU in an aqueous solution of 20 mL of pure water and 30 mL of dimethylformamide, and then add PP-g-GMA. Under mechanical stirring, heat the water bath to 80 °C and react for 8 h to obtain functionalized polyolefin fiber PP-g-GMA-GLU. Place the PP-g-GMA-GLU fiber in a 100 mg / L borate solution, fully oscillate it at room temperature for 2 h, and then place the PP-g-GMA-GLU fiber loaded with borate ions after full coordination in a dopamine cross-linking agent solution and cross-link it at 60 °C for 5 h. After the cross-linking reaction is completed, elute and remove the borate ions with 0.1 mol / L NaOH solution to obtain borate ion surface-imprinted fiber I-(PP-g-GMA-GLU).

[0039] Example 7

[0040] Soak 0.1 g of PE in a 100 mL solution system containing GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 for 24 h. The mass ratio of GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 is 25:15:35:1:0.3. After the soaked PP fibers are air-dried, place them in a low-temperature plasma device and irradiate them back and forth for 180 s in a high-purity helium atmosphere. After plasma polymerization is completed, quickly put the fibers into a 20 mL GMA solution and heat them in a water bath at 70 °C for 2 h to obtain modified polyolefin fibers PP-g-GMA. Dissolve 15 g of GLU in an aqueous solution of 15 mL of pure water and 35 mL of isopropanol, and then add PP-g-GMA. Under mechanical stirring, heat in a water bath to 70 °C and react for 10 h to obtain functionalized polyolefin fibers PP-g-GMA-GLU. Place the PP-g-GMA-GLU fibers in a 100 mg / L borate solution, shake them well at room temperature for 2 h, and then place the PP-g-GMA-GLU fibers loaded with borate ions after sufficient coordination in an N,N-dimethylformamide crosslinking agent solution and crosslink them at 70 °C for 6 h. After the crosslinking reaction is completed, elute with a 0.1 mol / L NaOH solution to remove the borate ions to obtain borate ion surface-imprinted fibers I-(PP-g-GMA-GLU).

[0041] Comparative Example 1

[0042] Commercially available activated carbon.

[0043] Comparative Example 2

[0044] Comparative Example 2 is set based on Example 2, and the difference is that the subsequent borate ion surface-imprinted polymerization treatment is not performed on the functionalized polyolefin fibers, and other conditions are the same as those in Example 2.

[0045] Soak 0.1 g of PP in a 100 mL solution system containing GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 for 24 h. The mass ratio of GMA, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4 is 25:15:35:1:0.3. After the soaked PP fibers are air-dried, place them in a low-temperature plasma device and irradiate them back and forth for 180 s in a high-purity air atmosphere. After plasma polymerization is completed, quickly put the fibers into a 15 mL GMA solution and heat them in a water bath at 60 °C for 2 h to obtain modified polyolefin fibers PP-g-GMA. Dissolve 10 g of NMDG in an aqueous solution of 10 mL of pure water and 40 mL of 1,4-dioxane, and then add PP-g-GMA. Under mechanical stirring, heat in a water bath to 80 °C and react for 7 h to obtain functionalized polyolefin fibers PP-g-GMA-NMDG.

[0046] Comparative Example 3

[0047] Comparative Example 3 was set based on Comparative Example 2, and the difference lies in that the functionalized polyolefin fiber was not subjected to subsequent surface imprinting polymerization treatment with borate ions, and other conditions were the same as those in Example 2.

[0048] Soak 0.1 g of PP in a 100 mL solution system containing GMA, water, ethanol, molar salt, and H2SO4 solution for 24 h. The mass ratio of GMA, water, ethanol, molar salt, and H2SO4 is: 25:15:35:1:0.3. After the soaked PP fibers are air-dried, they are placed in a low-temperature plasma device and irradiated back and forth for 180 s in a high-purity argon atmosphere. After plasma polymerization is completed, the fibers are quickly put into 15 mL of GMA solution and heated in a water bath at 60 °C for 2 h to obtain modified polyolefin fiber PP-g-GMA. Dissolve 10 g of polyethyleneimine (PEI) in 10 mL of pure water and 40 mL of an aqueous solution of 1,4-dioxane, and then add PP-g-GMA. Under mechanical stirring, heat in a water bath to 80 °C and react for 7 h to obtain functionalized polyolefin fiber PP-g-GMA-PEI.

[0049] Application Example 1

[0050] Place 0.01 g of each of the prepared samples in Examples 1-7 and Comparative Example 1 into 10 mL of a borate solution with a concentration of 100 mg / L, and measure the concentration of the borate solution at 0.5 h, 1 h, 2 h, and 3 h respectively to calculate the adsorption performance of the borate ion surface imprinted fiber for borate. The test method for the concentration of the borate solution is inductively coupled plasma method (ICP), and the instrument used is inductively coupled plasma emission spectrometer (ICAP6300). The results are shown in Table 1 below:

[0051] Table 1 Borate Ion Adsorption Test Results

[0052] 0.5h 1h 2h 3h Boric acid radical adsorption amount mg / g Boric acid radical adsorption amount mg / g Boric acid radical adsorption amount mg / g Boric acid radical adsorption amount mg / g Example 1 8.43 12.56 12.56 12.56 Example 2 10.33 15.42 15.42 15.42 Example 3 7.25 10.83 10.83 10.83 Example 4 6.93 10.16 10.16 10.16 Example 5 7.42 11.07 11.07 11.07 Example 6 8.38 12.51 12.51 12.51 Example 7 10.73 15.88 15.88 15.88 Comparative Example 1 0.67 1.24 2.07 2.07

[0053] Through the comparison of the data in the above examples and comparative examples, it is found that in the borate ion system, the adsorption rates of Examples 1-7 are relatively fast at 0-0.5 h, and then the adsorption rates gradually decrease, reaching adsorption equilibrium at about 60 min, and the maximum adsorption capacity reaches 15.88 mg / g. The adsorption rate of the boron adsorbent in Comparative Example 1 is not as fast as that in the examples, and it takes a longer time to reach adsorption equilibrium, and the final adsorption amount is also smaller than that in the examples. The boron adsorbent prepared by this patent method has the advantages of fast adsorption rate for borate ions, large adsorption capacity, and short time to reach adsorption equilibrium, which are all effects that the adsorbent in Comparative Example 1 cannot achieve. Through examples, it is shown that the boron adsorbent prepared by this method has certain advantages in terms of adsorption capacity, adsorption rate, etc.

[0054] Application Example 2

[0055] Put 0.01 g of each of the prepared samples in Examples 2 and Comparative Examples 2-3 into 10 mL of a multi-ion competition solution containing B(OH)4 - , SO4 2- , Na + , K + , Mg + with the concentration of each ion being 100 mg / L. After 2 h, measure the adsorption amount of each ion in the solution by each sample, and calculate the selective adsorption ability of the borate ion surface-imprinted fiber for borate. The test method for the content of each ion is inductively coupled plasma method (ICP), and the instrument used is inductively coupled plasma emission spectrometer (ICAP6300).

[0056] It was found through detection that the sample prepared in Example 2 had an adsorption amount of B(OH)4 - , SO4 2- , Na + , K + , Mg + accounting for 76.7%, 3.5%, 7%, 6.8%, and 6% of the total adsorption amount respectively; while the sample in Comparative Example 2 had an adsorption amount of B(OH)4 - , SO4 2- , Na + , K + , Mg + accounting for 48.3%, 13.2%, 14.8%, 10.9%, and 12.8% of the total adsorption amount respectively. The sample in Comparative Example 3 had an adsorption amount of B(OH)4 - , SO4 2- , Na + , K + , Mg + accounting for 29%, 12.9%, 20.3%, 18.4%, and 19.4% of the total adsorption amount respectively. From the above results, it can be seen that Example 2 has a specific adsorption function for borate, because the borate ion surface-imprinted fiber obtained after surface imprinting polymerization has a specific adsorption function for borate in the presence of multiple competing ions; while Comparative Example 3 has weaker specificity for borate than Comparative Example 2, because in the preparation of the functionalized polyolefin fiber in Comparative Example 2, NMDG with double hydroxyl functional groups was introduced, and the double hydroxyl functional groups are beneficial to the specific adsorption of borate.

Claims

1. A borate ion surface imprinted fiber, characterized in that, Using polyolefin fiber as the matrix, monomer A is grafted onto the surface of the polyolefin fiber, and then the amine group of monomer B reacts with the epoxy group of monomer A through a ring-opening reaction to be connected for functional modification. The functionalized product is coordinated to load borate ions, and then after reacting with a cross-linking agent, the borate ions are washed away to obtain borate ion surface-imprinted fibers; The monomer A is an ester compound containing an unsaturated acrylate group and an epoxy group; The monomer B is a molecule containing cis-ortho and meta-dihydroxy functional groups, and is specifically selected from one of glucosamine, N-methylglucamine, nucleosides, catecholamines, polysaccharides, glycoproteins, and glycopeptides; The mass ratio of the polyolefin fiber, monomer A, monomer B, and cross-linking agent is 1:50 - 200:40 - 150:50 - 550; The method for grafting monomer A onto the surface of the polyolefin fiber includes: fully impregnating the polyolefin fiber in the monomer A modification solution, drying the impregnated polyolefin fiber and then putting it into a low-temperature plasma device, and irradiating it back and forth in the monomer atmosphere to enable the polyolefin fiber to fully undergo a plasma polymerization reaction with monomer A, so that monomer A is grafted onto the surface of the polyolefin fiber.

2. The borate ion surface imprinted fiber according to claim 1, wherein The polyolefin fiber is an isotactic polymer with an average molecular weight of 180,000 - 300,000.

3. The borate ion surface imprinted fiber according to claim 1 or 2, characterized in that The polyolefin fiber is selected from one of polypropylene fiber, polyethylene fiber, polyvinyl chloride fiber, and polystyrene fiber.

4. The borate ion surface imprinted fiber according to claim 1, characterized in that The monomer A is glycidyl methacrylate.

5. The borate ion surface imprinted fiber according to claim 1, characterized in that, The cross-linking agent is one of dopamine, aniline, epichlorohydrin, N,N-dimethylformamide, and glutaraldehyde.

6. The preparation method of the borate ion surface imprinted fiber according to any one of claims 1-5, characterized in that, Specifically, it includes the following steps: (1) Fully impregnate the polyolefin fiber in the monomer A modification solution, dry the impregnated polyolefin fiber and then put it into a low-temperature plasma device, and irradiate it back and forth in the monomer atmosphere to enable the polyolefin fiber to fully undergo a plasma polymerization reaction with monomer A. After the reaction ends, place the polyolefin fiber in the monomer A modification solution again and react at 60 - 80 °C for 1 - 3 h to obtain modified polyolefin fibers; (2) Dissolve monomer B in a solvent, then add the modified polyolefin fiber in step (1), and react at 60 - 80 °C for 6 - 10 h. After the reaction ends, wash and dry to obtain functionalized polyolefin fibers; (3) Place the functionalized polyolefin fiber in step (2) in a borate solution, enable the functionalized polyolefin fiber to fully coordinate and load borate ions, then add a cross-linking agent to the solution, and carry out cross-linking at 50 - 70 °C for 2 - 6 h; after the cross-linking reaction ends, elute and remove the borate ions with an alkaline solution to obtain borate ion surface-imprinted fibers.

7. The preparation method of the borate ion surface imprinted fiber according to claim 6, characterized in that, The composition of the monomer A modification solution in step (1) is monomer A, water, ethanol, ammonium iron(II) sulfate hexahydrate, and H2SO4, where the mass ratio of ammonium iron(II) sulfate hexahydrate, monomer A, water, ethanol, and H2SO4 is 1:10 - 30:10 - 30:30 - 50:0.1 - 1.

8. The preparation method of the borate ion surface-imprinted fiber according to claim 6, characterized in that, The monomer atmosphere in step (1) is one of nitrogen, argon, helium, carbon dioxide, air, and oxygen.

9. The preparation method of the borate ion surface imprinted fiber according to claim 6, characterized in that The solvent in step (2) is one of water, 1,4-dioxane, isopropanol, and N,N-dimethylformamide or a mixture of two of them.