Supramolecular organic polymer and application thereof in adsorption of anionic pollutants

Abstract

The invention discloses a supramolecular organic polymer and application thereof in adsorption of anionic pollutants, and belongs to the technical field of wastewater adsorption materials. The supramolecular organic polymer is prepared from brominated pillar [5] arene and polyethyleneimine in different molar ratios. The supramolecular organic polymer prepared by the method provided by the invention has very many amino groups, so that the supramolecular organic polymer shows very high electropositivity in water, simultaneously has a large number of adsorption sites, and has a better adsorption effect on anion pollutants, especially iodide ions, azo dyes and the like.

Description

Technical Field

[0001] The invention relates to a supramolecular organic polymer and application thereof in adsorbing anionic pollutants, belonging to the technical field of wastewater adsorption materials. Background Art

[0002] In the process of industrialization and urbanization, a large amount of industrial wastewater, waste gas and solid residues are discharged into the environment, which seriously threatens human health and the ecological environment. This is mainly due to the presence of a large amount of heavy metal ions in these wastes, which inevitably migrate to the soil, groundwater and surface water. In addition, pesticides and fertilizers also contain trace amounts of heavy metal ions. These heavy metal ions migrate into plants through soil and water, affecting the growth and development of plants and reducing crop yields. This not only threatens the ecological balance, but also brings a series of adverse effects on human health, such as kidney and liver damage or other diseases.

[0003] Radioactive iodine can be released into the atmosphere in gaseous form, such as iodine (I2) or methyl iodide (CH3I), and accumulate in soil and water bodies through atmospheric transport and deposition. Exposure to high concentrations of radioactive iodine increases the risk of thyroid radioactive contamination, especially thyroid cancer, which poses a huge threat to human health. At the same time, radioactive iodine poses a serious threat to the global environment. Organic dyes, which are known for their color fastness and strength, have adverse effects on aquatic ecosystems, including destroying photosynthesis, affecting the quality of water bodies, and posing potential health risks to humans through the accumulation of toxic substances. Dyes with azo structures have carcinogenic, mutagenic and teratogenic properties, so effective treatments are urgently needed to mitigate their impact on the environment and health. The development of efficient and environmentally friendly adsorbents for the adsorption of these anionic pollutants has become a major trend in current environmental governance and waste treatment.

[0004] Traditional adsorption materials such as activated carbon and molecular sieves have problems such as low adsorption capacity, poor selectivity, and difficulty in regeneration, which restrict their promotion and application in real life, and also prompt people to seek new materials and technologies to solve these challenges. In this context, supramolecular polymers have attracted widespread attention as a potential material.

[0005] Supramolecular polymers are a class of polymers composed of non-covalent interactions between molecules. The structure constructed by non-covalent bonds has controllable adsorption properties and chemical stability, and can be applied to adsorption and separation processes under different environmental conditions. As a new type of adsorption material, supramolecular compounds can achieve efficient adsorption and separation of target molecules, and have broad application prospects in environmental governance, resource recovery, energy development and other fields. Compared with traditional covalent polymers, supramolecular polymers have more flexible structures and diverse properties, and their morphology and function can be adjusted under different conditions through non-covalent interactions such as hydrogen bonds, π-π filling, and van der Waals forces. Supramolecular compounds not only have excellent adsorption capacity and high selectivity, but also have chemical stability and easy structural modification, and can be used in adsorption separation, catalytic reactions, drug delivery and other fields.

[0006] Polyethyleneimine (PEI) is an ideal adsorption material. The content of primary, secondary and tertiary amine groups in polyethyleneimine molecules is high, so PEI has high efficiency and excellent adsorption performance. In addition, PEI has the advantages of low cost, non-toxicity and good biocompatibility. However, PEI has good water solubility and cannot be used alone as an adsorbent. Therefore, it is key to select a suitable ligand or a suitable carrier to form a polymer that is insoluble in water and organic solvents.

[0007] In summary, it is crucial for the current industrialization and urbanization process to develop new adsorbent materials that are highly selective and absorptive for anionic pollutants in printing and dyeing wastewater, especially materials that can adsorb anionic pollutants such as iodine ions and azo dyes. Summary of the invention

[0008] In view of the above problems existing in the prior art, the present invention uses different molar ratios of brominated column [5] aromatic hydrocarbons and polyethylene imine to prepare supramolecular organic polymers. The supramolecular organic polymers prepared by the present invention have a large number of amine groups, so they show a very high positive charge in water, and at the same time, there are a large number of adsorption sites, which have a good adsorption effect on anionic pollutants, especially iodine ions, azo dyes, etc.

[0009] The first object of the present invention is to provide a method for preparing a supramolecular organic polymer, comprising the following steps:

[0010] (1) dissolving the brominated column [5] aromatic hydrocarbon in a solvent and adding polyethyleneimine to obtain a reactant, heating the reactant, and condensing and refluxing to obtain a mixed solution;

[0011] (2) Cooling the mixed solution, filtering, washing, and drying to obtain the supramolecular organic polymer.

[0012] In one embodiment, the polyethyleneimine is linear polyethyleneimine or branched polyethyleneimine, preferably branched polyethyleneimine; the molecular weight of the linear polyethyleneimine is in the range of 600-20,000, preferably in the range of 10,000-20,000, and more preferably 20,000.

[0013] In one embodiment, in step (1), the molar ratio of the brominated column [5] aromatic hydrocarbon to polyethylene imine is (1-10): (1-10), preferably (1-5): (1-5), more preferably 1: (1-5), and more preferably 1:1.

[0014] In one embodiment, in step (1), the solvent includes one or more of anhydrous chloroform, dichloromethane, N,N-dimethylformamide, tetrahydrofuran, and methanol.

[0015] In one embodiment, in step (1), the mass volume ratio of the brominated column [5] aromatic hydrocarbon to the solvent is 0.1-2 g: 100-200 mL.

[0016] In one embodiment, in step (1), the reactants are heated to 100° C.-200° C., a protective gas is passed through, and condensation reflux is performed for 12 h-48 h to obtain a mixed solution.

[0017] In one embodiment, in step (2), the washing is first washing with methanol twice, filtering, and then washing with water twice.

[0018] In one embodiment, in step (2), the drying is vacuum drying at a temperature of 30°C-100°C for 1h-24h.

[0019] In one embodiment, the preparation method of the brominated pillar [5] arene is based on the preparation method in the paper (Yao Y, Xue M, Chi X, et al. A new water-soluble pillar [5] arene: synthesis and application in the preparation of gold nanoparticles. Chem Commun (Camb). 2012 Jul 4; 48 (52): 6505-7.) or the preparation method of the bromoethoxy pillar [5] arene in patent CN118448684A, comprising the following steps:

[0020] (1) Preparation of brominated aromatic hydrocarbons:

[0021] Add hydroquinone di(2-hydroxyethyl) ether to a solvent, and add triphenylphosphine and a catalyst thereto, react at 18-25°C for 2-6 hours, add water and shake after the reaction is completed, filter, rotary evaporate the filtrate, and dry to obtain a monomer;

[0022] (2) Add the monomer obtained in step (1) to 1,2-dichloroethane, add polyformaldehyde and boron trifluoride ether thereto, and react at 18 to 25° C. for 1 to 3 hours. After the reaction is completed, extract, dry, filter, and rotary evaporate the filtrate to obtain crystals. After the crystals are dried, brominated column [5] aromatic hydrocarbons are obtained.

[0023] In one embodiment, in step (1), the solvent is acetonitrile and the catalyst is carbon tetrabromide.

[0024] In one embodiment, in step (2), the filtrate is rotary evaporated at 40-60° C., and the crystals obtained by rotary evaporation are dried for 1-3 hours to obtain brominated column [5] aromatic hydrocarbons.

[0025] In one embodiment, the method for preparing brominated column [5] aromatics further comprises the following steps:

[0026] (1) Synthesis of brominated aromatics

[0027] Hydroquinone di(2-hydroxyethyl) ether (10 g, 50.4 mmol) was dissolved in acetonitrile (250 mL), and triphenylphosphine (31.5 g, 120 mmol) was added to the solution. Then, carbon tetrabromide (39.8 g, 120 mmol) was added to the solution under stirring. The mixture was stirred at 25° C. for 4 hours to complete the reaction. After the reaction was completed, an appropriate amount of cold deionized water was added to the solution after the reaction, and the mixture was shaken until a solid appeared in the flask. The obtained precipitate was collected by filtration and washed with methanol. The washing liquid was filtered again to remove impurities. The obtained filtrate was subjected to rotary evaporation at 40° C., and the solid obtained by rotary evaporation was dried at 60° C. to obtain the monomer;

[0028] (2) Synthesis of brominated aromatics

[0029] The first step product (3.37 g, 11.5 mmol) was dissolved in 1,2-dichloroethane (50 mL), and paraformaldehyde (0.349 g, 11.5 mmol) was added to the solution. After the substrate was dissolved, the catalyst boron trifluoride etherate (BF3O(C2H5)2, 2.9 mL, 23 mmol) was added, and the mixture was stirred at 25°C for 2 hours to complete the reaction. After the reaction was completed, the mixture was fully extracted twice with deionized water, and the collected organic phase was dried with an appropriate amount of anhydrous sodium sulfate and filtered to obtain a filtrate. The solvent was rotary evaporated at 50°C and the crystals were dried to obtain brominated column [5] aromatic hydrocarbons.

[0030] In one embodiment, the method for preparing the supramolecular organic polymer further comprises the following steps:

[0031] The brominated column [5] aromatic hydrocarbon is dissolved in a solvent and polyethyleneimine is added, the reaction system is heated to a certain temperature in an oil bath, and condensed and refluxed under the protection of nitrogen for a certain time. After the reaction is completed, the mixed solution is cooled and filtered, and the residue is fully washed with methanol and water and filtered to obtain a brown-red solid. After vacuum drying at a certain temperature for a certain time, a brown-red powdery supramolecular organic polymer (PEI-P5) is obtained;

[0032] The polyethyleneimine is a linear polyethyleneimine or a branched polyethyleneimine.

[0033] The second object of the present invention is to provide a supramolecular organic polymer obtained by the above preparation method.

[0034] The third object of the present invention is to provide a use of the supramolecular organic polymer in adsorbing pollutants.

[0035] In one embodiment, the pollutants are anionic pollutants in wastewater, including one or more of iodide ion, methyl orange, acid chrome blue K, and eosin B.

[0036] A fourth object of the present invention is to provide a method for adsorbing iodide ions, wherein the method uses the supramolecular organic polymer of the present invention.

[0037] In one embodiment, the method is to adsorb for 5 to 13 hours at 18 to 25° C. when the system is an iodine solution with a pH of 3 to 9 and an initial concentration of 0.39 to 0.94 mmol / L.

[0038] In one embodiment, the method is to adsorb for 9 to 13 hours at 18 to 25° C. when the pH of the iodine solution is preferably 5 to 8 and the initial concentration is 0.70 to 0.94 mmol / L.

[0039] In one embodiment, the method is to adsorb for 13 hours at 18-25° C. when the system further preferably has an iodine solution pH of 7 and an initial concentration of 0.86 mmol / L.

[0040] A fifth object of the present invention is to provide a method for adsorbing Eosin B, which method uses the supramolecular organic polymer of the present invention.

[0041] In one embodiment, the method is to adsorb for 4 to 13 hours at 18 to 25° C. when the pH of the system is 3 to 9 and the initial concentration is 1 to 6 mmol / L.

[0042] In one embodiment, the method is to adsorb the dye at 18-25° C. for 9-13 hours when the pH of the system is preferably 3-7 and the initial concentration is 3-6 mmol / L.

[0043] In one embodiment, the method is to adsorb for 13 hours at 18-25° C. when the pH of the system is further preferably 7 and the initial concentration of Eosin B dye is 5 mmol / L.

[0044] A sixth object of the present invention is to provide a method for improving the pollutant adsorption capacity of supramolecular organic polymers, comprising the following steps:

[0045] (1) dissolving the brominated column [5] aromatic hydrocarbon in a solvent and adding polyethyleneimine to obtain a reactant, heating the reactant, and condensing and refluxing to obtain a mixed solution;

[0046] (2) Cooling the mixed solution, filtering, washing, and drying to obtain the supramolecular organic polymer.

[0047] Beneficial Effects

[0048] (1) The present invention combines brominated column [5] aromatic hydrocarbons with polyethylene imine to obtain a supramolecular organic polymer having numerous amine groups. The supramolecular organic polymer exhibits a very high positive charge in water and can attract anionic pollutants and combine with them by electrostatic attraction.

[0049] (2) The supramolecular organic polymer prepared by the present invention can be reused through desorption, has no destructive effect on the structure of organic matter, has stable adsorption performance, and is environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 This is the NMR image of the brominated column [5] aromatic hydrocarbon of the present invention.

[0051] Figure 2 This is the infrared spectrum of the supramolecular organic polymer in Example 1 of the present invention.

[0052] Figure 3 This is a scanning electron microscope image of the supramolecular organic polymer in Example 1 of the present invention.

[0053] Figure 4 This is a graph showing the effect of pH value on the adsorption performance of iodine solution adsorbed by the supramolecular organic polymer in Example 1 of the present invention.

[0054] Figure 5 This is a graph showing the effect of the initial concentration of the supramolecular organic polymer on the adsorption of iodine solution in Example 1 of the present invention.

[0055] Figure 6 This is a graph showing the effect of the adsorption time of the supramolecular organic polymer on the iodine solution in Example 1 of the present invention.

[0056] Figure 7This is a graph showing the adsorption percentage of different dyes by the supramolecular organic polymer in Example 1 of the present invention.

[0057] Figure 8 This is a graph showing the effect of pH value on the adsorption performance of Eosin B dye by the supramolecular organic polymer in Example 1 of the present invention.

[0058] Fig. 9 This is a graph showing the effect of the initial concentration of the supramolecular organic polymer on the adsorption of Eosin B dye in Example 1 of the present invention.

[0059] Fig.10 This is a graph showing the effect of the adsorption time of the supramolecular organic polymer on the Eosin B dye in Example 1 of the present invention.

[0060] Fig.11 The interference experiment results of the supramolecular organic polymer in Example 1 of the present invention are shown, including: (a) the effect of ionic strength on the removal of I2 / KI by Eosin B (EB) dye and PEI-P5; (b) the effect of competing ions on the removal of Eosin B (EB) dye and I2 / KI; (c) the effect of humic acid on the removal of Eosin B (EB) dye and I2 / KI; (d) the adsorption efficiency of low concentration Eosin B (EB) dye and I2 / KI solution.

[0061] Fig.12 Schematic diagram of the supramolecular organic polymer structure of the present invention. DETAILED DESCRIPTION

[0062] 1. The detection methods involved in the following embodiments:

[0063] (1) NMR

[0064] Take 10-25 mg of sample and put it into CDCl3, dissolve it completely and put it into NMR tube, then use full digital NMR spectrometer (AduanceⅢ400MH Z ) for nuclear magnetic resonance testing.

[0065] (2) Scanning electron microscopy

[0066] The surface characteristics of the samples were observed using a scanning electron microscope (su1510). Before testing, the samples were smeared on an electron microscope stage with conductive glue, and then gold-sprayed. The gold-sprayed electron microscope stage was placed in an electron microscope instrument for observation.

[0067] (3) Fourier transform infrared spectroscopy test

[0068] The sample powder was tableted: 2 mg of the sample was mixed with 200 mg of potassium bromide powder and ground evenly, and tableted using a tablet press; the obtained tablets were placed in a Fourier transform infrared spectrometer (Nicolet is10) for infrared testing.

[0069] 2. Raw materials in the embodiments:

[0070] Polyethyleneimine-1800 (PEI-1800), polyethyleneimine-10000 (PEI-10000), polyethyleneimine-20000 (PEI-20000), and branched polyethyleneimine-25000 (BPEI-25000) were all purchased from Shanghai MacLean Biochemical Technology Co., Ltd. The branched polyethyleneimine involved in the examples is branched polyethyleneimine-25000 purchased from Shanghai MacLean Biochemical Technology Co., Ltd.

[0071] The preparation method of brominated pillar [5]arene is based on the preparation method in the paper (Yao Y, Xue M, Chi X, et al. A new water-soluble pillar [5]arene: synthesis and application in the preparation of gold nanoparticles. Chem Commun (Camb). 2012 Jul 4; 48 (52): 6505-7.) or the preparation method of bromoethoxy pillar [5]arene in patent CN118448684A, which specifically includes the following steps:

[0072] (1) Preparation of brominated aromatic hydrocarbons:

[0073] Hydroquinone di(2-hydroxyethyl) ether (10 g, 50.4 mmol) was added to 250 mL of acetonitrile, and triphenylphosphine (31.5 g, 120 mmol) was added thereto, and then carbon tetrabromide (39.8 g, 120 mmol) was added thereto under stirring at 2000 rpm, and the reaction was completed by stirring at 2000 rpm for 4 h at 25°C. After the reaction was completed, 50×2 mL of cold deionized water (4-10°C) was added thereto, and the mixture was shaken until solid appeared, filtered, and the precipitate was collected and washed with methanol twice. The washing liquid was filtered again to remove impurities, and the filtrate was subjected to rotary evaporation at 40°C, and the solid obtained by rotary evaporation was dried at 60°C to obtain the monomer;

[0074] (2) The monomer (3.37 g, 11.5 mmol) obtained in step (1) was added to 50 mL of 1,2-dichloroethane, and paraformaldehyde (0.349 g, 11.5 mmol) was added thereto. After stirring at 2000 rpm to dissolve it, a catalyst of boron trifluoride etherate (BF3O(C2H5)2, 2.9 mL, 23 mmol) was added, and the reaction was completed by stirring at 25°C for 2 hours. After the reaction was completed, the mixture was extracted twice with deionized water, and the organic phase was collected. The collected organic phase was dried with 50 g of anhydrous sodium sulfate and filtered to obtain a filtrate. The filtrate was rotary evaporated at 50°C, and the crystals obtained by rotary evaporation were dried for 2 hours to obtain brominated column [5] aromatic hydrocarbons.

[0075] The prepared brominated column [5] aromatic hydrocarbons were characterized by NMR. Figure 1 As shown, the details are as follows:

[0076] 1 H NMR (400MHz, CDCl3) δ6.93 (s, 10H), 4.24 (t, J = 5.7Hz, 20H), 3.84 (s, 10H), 3.66 (t, J = 5.7Hz, 2H).

[0077] Example 1: A supramolecular organic polymer

[0078] The specific preparation method comprises the following steps:

[0079] (1) 1 mol of brominated column [5] aromatic hydrocarbon is added to 50 mL of N,N-dimethylacetamide (DMAC), and 1 mol of polyethyleneimine (molecular weight: 1800) is added thereto and dissolved to obtain a reactant, the reactant is heated to 160° C. in an oil bath, and nitrogen is introduced, and the mixture is condensed and refluxed for 12 h to obtain a mixed solution;

[0080] (2) The mixed solution was cooled to 25° C. and then filtered. The filter residue was washed twice with methanol, filtered, and then washed twice with water and filtered to obtain a brown-red solid. The brown-red solid was vacuum dried at 100° C. for 12 h to obtain a brown-red powder, which was the supramolecular organic polymer (PEI-P5-1).

[0081] The characterization results of PEI-P5-1 are as follows: Figure 2 and Figure 3 shown.

[0082] Example 2: A supramolecular organic polymer

[0083] Specific implementation method The method is the same as Example 1, except that the amount of polyethyleneimine (molecular weight: 1800) is changed to 5 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-2).

[0084] Example 3: A supramolecular organic polymer

[0085] Specific implementation method The method is the same as Example 1, except that the amount of polyethyleneimine (molecular weight: 1800) is changed to 10 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-3).

[0086] Example 4: A supramolecular organic polymer

[0087] Specific implementation method The method is the same as Example 1, except that the amount of brominated column [5] aromatic hydrocarbon is changed to 5 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-4).

[0088] Example 5: A supramolecular organic polymer

[0089] Specific implementation method The method is the same as Example 1, except that the amount of brominated column [5] aromatic hydrocarbon is changed to 10 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-5).

[0090] Example 6: A supramolecular organic polymer

[0091] The specific implementation method is the same as Example 1, except that polyethyleneimine (molecular weight: 1800) is replaced with polyethyleneimine (molecular weight: 10000), and other conditions remain unchanged, comprising the following steps:

[0092] (1) 1 mol of brominated column [5] aromatic hydrocarbon is added to 50 mL of N,N-dimethylacetamide (DMAC), and 1 mol of polyethyleneimine (molecular weight: 10,000) is added thereto and dissolved to obtain a reactant, the reactant is heated to 160° C. in an oil bath, and nitrogen is introduced, and the reaction is condensed and refluxed for 12 hours to obtain a mixed solution;

[0093] (2) The mixed solution was cooled to 25° C. and then filtered. The filter residue was washed twice with methanol, filtered, and then washed twice with water and filtered to obtain a brownish red solid. The brownish red solid was vacuum dried at 100° C. for 12 h to obtain a brownish red powder, which was the supramolecular organic polymer (PEI-P5-6).

[0094] Example 7: A supramolecular organic polymer

[0095] The specific implementation method is the same as Example 6, except that the amount of polyethyleneimine (molecular weight: 10000) is changed to 5 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-7).

[0096] Example 8: A supramolecular organic polymer

[0097] The specific implementation method is the same as Example 6, except that the amount of polyethyleneimine (molecular weight: 10000) is changed to 10 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-8).

[0098] Example 9: A supramolecular organic polymer

[0099] The specific implementation method is the same as Example 6, except that the amount of brominated column [5] aromatic hydrocarbon is changed to 5 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-9).

[0100] Example 10: A supramolecular organic polymer

[0101] The specific implementation method is the same as Example 6, except that the amount of brominated column [5] aromatic hydrocarbon is changed to 10 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-10).

[0102] Example 11: A supramolecular organic polymer

[0103] The specific implementation method is the same as Example 1, except that polyethyleneimine (molecular weight: 1800) is replaced with polyethyleneimine (molecular weight: 20000), and other conditions remain unchanged, comprising the following steps:

[0104] (1) 1 mol of brominated column [5] aromatic hydrocarbon is added to 50 mL of N,N-dimethylacetamide (DMAC), and 1 mol of polyethyleneimine (molecular weight: 20,000) is added thereto and dissolved to obtain a reactant, the reactant is heated to 160° C. in an oil bath, and nitrogen is introduced, and the reaction is condensed and refluxed for 12 hours to obtain a mixed solution;

[0105] (2) The mixed solution was cooled to 25° C. and then filtered. The filter residue was washed twice with methanol, filtered, and then washed twice with water and filtered to obtain a brownish red solid. The brownish red solid was vacuum dried at 100° C. for 12 h to obtain a brownish red powder, which was the supramolecular organic polymer (PEI-P5-11).

[0106] Example 12: A supramolecular organic polymer

[0107] Specific implementation method is the same as Example 11, except that the amount of polyethyleneimine (molecular weight: 20000) is changed to 5 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-12).

[0108] Example 13: A supramolecular organic polymer

[0109] The specific implementation method is the same as Example 11, except that the amount of polyethyleneimine (molecular weight: 20,000) is changed to 10 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-13).

[0110] Example 14: A supramolecular organic polymer

[0111] The specific implementation method is the same as Example 11, except that the amount of brominated column [5] aromatic hydrocarbon is changed to 5 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-14).

[0112] Example 15: A supramolecular organic polymer

[0113] The specific implementation method is the same as Example 11, except that the amount of brominated column [5] aromatic hydrocarbon is changed to 10 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-15).

[0114] Example 16: A supramolecular organic polymer

[0115] The specific implementation method is the same as Example 1, except that polyethyleneimine (molecular weight: 1800) is replaced by branched polyethyleneimine, and other conditions remain unchanged, comprising the following steps:

[0116] (1) 1 mol of brominated column [5] aromatic hydrocarbon is added to 50 mL of N,N-dimethylacetamide (DMAC), and 1 mol of branched polyethyleneimine is added thereto to dissolve the reactant, the reactant is heated to 160° C. in an oil bath, and nitrogen is introduced, and the reaction is condensed and refluxed for 12 hours to obtain a mixed solution;

[0117] (2) The mixed solution was cooled to 25° C. and then filtered. The filter residue was washed twice with methanol, filtered, and then washed twice with water and filtered to obtain a brownish red solid. The brownish red solid was vacuum dried at 100° C. for 12 h to obtain a brownish red powder, which was the supramolecular organic polymer (PEI-P5-16).

[0118] Example 17: A supramolecular organic polymer

[0119] The specific implementation method is the same as Example 16, except that the amount of branched polyethyleneimine is changed to 5 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-17).

[0120] Example 18: A supramolecular organic polymer

[0121] The specific implementation method is the same as Example 16, except that the amount of branched polyethyleneimine is changed to 10 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-18).

[0122] Example 19: A supramolecular organic polymer

[0123] The specific implementation method is the same as Example 16, except that the amount of brominated column [5] aromatic hydrocarbon is changed to 5 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-19).

[0124] Example 20: A supramolecular organic polymer

[0125] The specific implementation method is the same as Example 16, except that the amount of brominated column [5] aromatic hydrocarbon is changed to 10 mol, and other conditions remain unchanged to prepare a supramolecular organic polymer (PEI-P5-20).

[0126] Adsorption of iodide ions in iodine solution by supramolecular organic polymers prepared in Examples 1 to 20

[0127] 1. Optimization of the adsorption conditions of iodine solution by the supramolecular organic polymer (PEI-P5-1) prepared in Example 1

[0128] Taking iodine ions in iodine solution as adsorption objects, the adsorption effect of PEI-P5-1 prepared in Example 1 under different pH values, iodine concentrations and adsorption times of iodine solutions was investigated, as follows:

[0129] (1) pH value

[0130] Weigh 10 mg of PEI-P5-1 prepared in Example 1, take 100 mL of iodine solution with an initial concentration of 0.39 mmol / L (pH 7), and adjust the pH of the iodine solution to 3, 5, 6, 7, 8, 9, and 11 by adding different amounts of 0.1 mol / L hydrochloric acid aqueous solution and 0.1 mol / L NaOH aqueous solution. Add the adsorbent material obtained in Example 1 to iodine solutions of various pH values, and place it in a constant temperature oscillating water bath at 25°C. After oscillating and adsorbing at 500 rpm for 24 hours, the adsorption of iodine solutions of different pH values ​​by the supramolecular organic polymer was tested by ultraviolet absorption spectroscopy.

[0131] The results are as follows Figure 4 As shown in Table 1:

[0132] Table 1 Iodine adsorption results of PEI-P5-1 prepared in Example 1 at different iodine solution pH

[0133] pH value of iodine solution Iodine removal rate (%) 3 87.6 5 94.3 6 96.7 7 98.9 8 94.3 9 82.9 11 51.1

[0134] It can be seen that when the pH of the iodine solution is 7, the iodine removal rate is the highest and the adsorption effect is the best.

[0135] (2) Iodine concentration

[0136] Weigh 10 mg of PEI-P5-1 prepared in Example 1, and take 100 mL of iodine solutions with initial concentrations of 0.39 mmol / L, 0.47 mmol / L, 0.55 mmol / L, 0.62 mmol / L, 0.70 mmol / L, 0.78 mmol / L, 0.86 mmol / L, and 0.94 mmol / L, respectively. When the pH value is 7.0, add the PEI-P5-1 of Example 1 to the iodine solutions of various concentrations, and place them in a constant temperature oscillating water bath at 25°C. After adsorption at 500 rpm for 24 hours, the adsorption of supramolecular organic polymers to iodine solutions of different concentrations is tested by ultraviolet absorption spectroscopy.

[0137] The results are as follows Figure 5 As shown in Table 2:

[0138] Table 2 Iodine adsorption results of PEI-P5-1 prepared in Example 1 at different initial concentrations of iodine solution

[0139] Initial concentration of iodine solution (mmol / L) Iodine adsorption (mg / g) 0.39 1059.42365 0.47 1158.98923 0.55 1263.71168 0.62 1364.29163 0.70 1444.15907 0.78 1507.45725 0.86 1525.29952 0.94 1530.36563

[0140] It can be seen that when the initial concentration of iodine solution is 0.86mmol / L, the iodine adsorption reaches adsorption equilibrium and the adsorption effect is optimal.

[0141] (3) Adsorption time

[0142] Weigh 10 mg of PEI-P5-1 of Example 1, and take 100 mL of iodine solution with an initial concentration of 0.86 mmol / L respectively. At pH 7.0, place the PEI-P5-1 of Example 1 in a constant temperature oscillating water bath at 25° C., and adsorb at 500 rpm for 13 h. Then, the adsorption of iodine solution by the supramolecular organic polymer was tested by ultraviolet absorption spectroscopy every 1 h.

[0143] The results are as follows Figure 6 As shown in Table 3:

[0144] Table 3 Iodine adsorption results of PEI-P5-1 prepared in Example 1 at different adsorption times

[0145]

[0146]

[0147] It can be seen that the iodine adsorption amount increased dramatically from 0 to 10 hours, and then tended to be stable. The iodine adsorption amount at 11 hours was relatively more stable.

[0148] In summary, when the pH of the iodine solution is 7, the initial concentration is 0.86 mmol / L, and the adsorption is carried out at a constant temperature of 25°C for 11 h, the adsorption effect of PEI-P5-1 prepared in Example 1 is the best.

[0149] 2. Adsorption of iodine solution by supramolecular organic polymers under optimal conditions (iodine solution at pH 7, initial concentration of 0.86 mmol / L, constant temperature adsorption at 25°C for 11 h)

[0150] The supramolecular organic polymers prepared in Examples 1 to 20 were subjected to adsorption of iodine solution under the above-mentioned optimal conditions (iodine solution at pH 7, initial concentration of 0.86 mmol / L, constant temperature adsorption at 25° C. for 11 h), as follows:

[0151] 10 mg of the supramolecular organic polymer prepared in Examples 1 to 20 was weighed respectively, and 100 mL of an iodine solution with an initial concentration of 0.86 mmol / L was taken respectively. At pH 7.0, the adsorbent materials of Examples 1 to 20 were added to the iodine solution respectively, and placed in a constant temperature oscillating water bath at a temperature of 25° C. After oscillating and adsorbing at 500 rpm for 11 hours, the adsorption results of the supramolecular organic polymer on the iodine solution were tested by ultraviolet absorption spectroscopy (Table 8).

[0152] Adsorption of dyes by supramolecular organic polymers prepared in Examples 1 to 20

[0153] 1. Adsorption of 7 dyes by the supramolecular organic polymer prepared in Example 1

[0154] The supramolecular organic polymer prepared in Example 1 was tested for adsorption of seven dyes, namely Congo red (CR), thymol blue (TB), methylene blue (MB), methyl orange (MO), acid chrome blue K (ABK), eosin B (EB), and crystal violet (VB), as follows:

[0155] Weigh 10 mg of PEI-P5-1 prepared in Example 1, take 10 mL of the above 7 dye solutions with an initial concentration of 0.5 mmol / L respectively, add PEI-P5-1 of Example 1 to the 7 dye solutions at a pH of 7.0, and place in a constant temperature oscillating water bath at a temperature of 25°C. After oscillating and adsorbing at 500 rpm for 24 hours, the adsorption results of PEI-P5-1 prepared in Example 1 on the 7 dyes were tested by ultraviolet absorption spectroscopy.

[0156] The results are as follows Figure 7 As shown in Table 4:

[0157] Table 4 Adsorption results of PEI-P5-1 prepared in Example 1 on different dyes

[0158] dye Dye removal rate (%) Congo Red 97.2 Thymol blue 85.5 Methylene blue 2.6 Methyl Orange 88.6 Acid Chrome Blue K 96.8 Eosin B 98.7 Crystal violet 49.6

[0159] It can be seen that Eosin B dye has the highest removal rate, so Eosin B was selected as the dye in the following steps to optimize the adsorption conditions.

[0160] 2. Optimization of the adsorption conditions of Eosin B dye by the supramolecular organic polymer (PEI-P5-1) prepared in Example 1

[0161] Taking Eosin B as the adsorption object, the adsorption effect of PEI-P5-1 prepared in Example 1 was investigated under different pH values ​​of Eosin B dye, dye solution concentrations, and adsorption times, as follows:

[0162] (1) pH value

[0163] Weigh 10 mg of PEI-P5-1 of Example 1, and take 10 mL of Eosin B dye with an initial concentration of 0.5 mmol / L respectively. By adding different amounts of 0.1 mol / L hydrochloric acid aqueous solution and 0.1 mol / L NaOH aqueous solution, the pH of the Eosin B dye is adjusted to 3, 5, 6, 7, 8, 9, and 11 respectively. The adsorption material obtained in Example 1 is added to the Eosin B dye of each pH value, and placed in a constant temperature oscillating water bath at a temperature of 25°C. After oscillating and adsorbing at 500 rpm for 24 hours, the adsorption of Eosin B of different pH values ​​by the supramolecular organic polymer is tested by ultraviolet absorption spectroscopy.

[0164] The results are as follows Figure 8 As shown in Table 5:

[0165] Table 5 Eosin B dye adsorption results of PEI-P5-1 prepared in Example 1 at different dye pH

[0166] Eosin B Dye pH Eosin B removal rate (%) 3 97.6 5 98.4 6 98.5 7 98.8 8 96.4 9 91.1 11 49.7

[0167] It can be seen that when the pH of Eosin B dye is 7, the removal rate of Eosin B is the largest and the adsorption effect is the best.

[0168] (2) Dye concentration

[0169] Weigh 10 mg of PEI-P5-1 of Example 1, and take 10 mL of Eosin B dye with initial concentrations of 0.71 mmol / L, 1.41 mmol / L, 2.06 mmol / L, 3.02 mmol / L, 4.22 mmol / L, 5.40 mmol / L, and 6.40 mmol / L, respectively. At pH 7.0, the adsorbent material obtained in Example 1 was added to each concentration of Eosin B dye, and placed in a constant temperature shaking water bath at 25°C. After adsorption at 500 rpm for 24 hours, the adsorption of Eosin B dye of different concentrations by the supramolecular organic polymer was tested by ultraviolet absorption spectroscopy.

[0170] The results are as follows Fig. 9 As shown in Table 6:

[0171] Table 6 Eosin B dye adsorption results of PEI-P5-1 prepared in Example 1 at different initial concentrations of Eosin B dye

[0172] Eosin B dye initial concentration (mmol / L) Eosin B dye adsorption (mg / g) 0.71 438.74372 1.41 749.30153 2.06 856.45274 3.02 995.34521 4.22 1028.3073 5.40 1109.54054 6.40 1109.42655

[0173] It can be seen that when the initial concentration of Eosin B dye is 5mmol / L, the adsorption amount of Eosin B is the largest and the adsorption effect is the best.

[0174] (3) Adsorption time

[0175] Weigh 10 mg of PEI-P5-1 of Example 1 and 10 mL of Eosin B dye with an initial concentration of 5 mmol / L. At pH 7.0, place the PEI-P5-1 of Example 1 in a constant temperature oscillating water bath at 25°C. After adsorption at 500 rpm for 15 hours, the adsorption of Eosin B dye by the supramolecular organic polymer was tested by ultraviolet absorption spectroscopy every 1 hour.

[0176] The results are as follows Fig.10 As shown in Table 7:

[0177] Table 7 Eosin B dye adsorption results of PEI-P5-1 prepared in Example 1 at different adsorption times

[0178]

[0179]

[0180] It can be seen that the adsorption of Eosin B increased dramatically from 0 to 10 hours, and then tended to be stable. The adsorption of Eosin B at 14 hours was relatively more stable.

[0181] In summary, when the pH value of Eosin B dye was 7, the initial concentration was 5 mmol / L, and the adsorption was carried out at a constant temperature of 25° C. for 14 h, the adsorption effect of PEI-P5-1 prepared in Example 1 was the best.

[0182] 3. Adsorption of Eosin B dye by supramolecular organic polymers under the optimal conditions (pH 7, initial concentration 5 mmol / L, constant temperature adsorption at 25°C for 14 h)

[0183] The supramolecular organic polymers prepared in Examples 1 to 20 were used to adsorb Eosin B dye under the above-mentioned optimal conditions (when the pH of Eosin B dye was 7 and the initial concentration was 5 mmol / L, constant temperature adsorption was performed at 25° C. for 14 h), as follows:

[0184] 10 mg of the supramolecular organic polymer prepared in Examples 1 to 20 was weighed respectively, and 10 mL of Eosin B dye with an initial concentration of 5 mmol / L was taken respectively. At pH 7.0, the adsorption materials of Examples 1 to 20 were added to the Eosin B dye, and placed in a constant temperature shaking water bath at a temperature of 25° C. After oscillating and adsorbing at 500 rpm for 14 hours, the adsorption results of the supramolecular organic polymer on Eosin B dye were tested by ultraviolet absorption spectroscopy.

[0185] Table 8 Adsorption results of supramolecular organic polymers prepared in Examples 1 to 20 on iodine solution and eosin B dye

[0186]

[0187]

[0188] From Table 8, it can be seen that the adsorption results of the supramolecular organic polymers prepared in Examples 1 to 20 on iodine solution and Eosin B dye are:

[0189] Example 16 is a preferred embodiment of the present invention. The difference between Examples 1-5 is that the molar ratio of brominated column [5] aromatic hydrocarbons and polyethylene imine is different. When the molar ratio is 1:1, the adsorption effect is optimal. Increasing the amount of polyethylene imine or the amount of brominated column [5] aromatic hydrocarbons will lead to a decrease in the removal rate of iodine ions and EB dyes by the adsorbent material, because the amino group on polyethylene imine has a strong positive charge and can attract iodine anions. Similarly, the benzene ring on the brominated column [5] aromatic hydrocarbons will produce an iodine benzene effect with iodine ions and produce mutual attraction. In addition, brominated column [5] aromatic hydrocarbons can also attract anionic dyes EB through the non-covalent bond interaction of π-π stacking. When the ratio of polyethylene imine to brominated column [5] aromatic hydrocarbons is 1:5 and 1:10, the brominated column [5] aromatic hydrocarbons in the adsorbent material occupy a large number of amine groups, resulting in a decrease in its positive charge.

[0190] When the ratio of polyethyleneimine to brominated column [5] aromatic hydrocarbon is 5:1 or 10:1, the number of brominated column [5] aromatic hydrocarbon as a linking group is reduced, resulting in a weak bond and a decrease in the molecular weight of the polymer, which leads to a decrease in the adsorption amount. When the molecular weight of polyethyleneimine is increased, its adsorption performance will be significantly improved, while when the molecular weight is too large, its bonding force is not strong, the molecular weight of the polymer is reduced, and the adsorption performance is reduced.

[0191] Branched polyethyleneimine has better adsorption performance for anionic pollutants than other straight-chain polyethyleneimines because its branches carry many amine groups, and the resulting polymers are strong and have a large molecular weight; they can also combine with more brominated column[5] aromatic hydrocarbons, resulting in better adsorption effects.

[0192] Interference experiment

[0193] Scheme 1: In order to study the effect of ionic strength on the adsorption of EB dye and I2 / KI solution by PEI-P5-1 in Example 1, NaCl (0 g / L, 0.1 g / L, 0.25 g / L, 0.5 g / L, 1 g / L) was added to 0.5 mM Eosin B (EB) dye and 0.39 mM I2 / KI solution, followed by adsorption by PEI-P5-1 (10 mg) in Example 1, and the removal rate was determined using Formula 1.

[0194] Scheme 2: In order to study the effect of competitive ions on the adsorption of EB dye and I2 / KI solution by PEI-P5-1 in Example 1, equal amounts of KCl, KBr, KNO3 and K2SO4 (the total competitive anion Cl - Br - 、NO3 - and SO4 2- The concentrations were 0 g / L, 0.1 g / L, 0.25 g / L, 0.5 g / L, and 1 g / L), and the solution was subsequently adsorbed with PEI-P5-1 (10 mg), and the removal rate was calculated by Formula 1.

[0195] Scheme 3: In order to investigate the effect of humic acid on the adsorption of EB dye and I2 / KI solution by PEI-P5-1 in Example 1, 0.5 mM EB dye and 0.39 mM I2 / KI solution were mixed with humic acid (0 g / L, 0.1 g / L, 0.25 g / L, 0.5 g / L, 1 g / L) and adsorbed with PEI-P5-1 (10 mg). After adsorption equilibrium, humic acid impurities were filtered out to obtain a clear solution, and the removal rate was calculated by Formula 1.

[0196] Scheme 4: Since the dye and radioactive iodine have considerable environmental mobility, the concentration of dye and iodine in groundwater reaches one part per million (sub-ppm). Therefore, in order to further determine the adsorption efficiency of trace I2, PEI-P5-1 (10 mg) of Example 1 was immersed in EB dye and I2 / KI solution (50 ppb, 100 ppb, 200 ppb, 500 ppb and 1000 ppb, 100 mL), stirred at room temperature for 24 h, and adsorption experiments were carried out. The removal rate was calculated by formula (1).

[0197]

[0198] Where λ1 is the absorbance of the residual dye solution measured after adsorption, and λ0 represents the initial absorbance of the dye solution before contacting the adsorbent.

[0199] result:

[0200] The result of option 1 is as follows Fig.11(a) as shown:

[0201] With the increase of NaCl concentration, the removal rates of EB dye and I2 / KI decreased.

[0202] For PEI-P5-1, when the NaCl concentration was 0 g / L, the removal rates of EB dye and I2 / KI were 98.70% and 98.90%, respectively; when the NaCl concentration was 1 g / L, the removal rates of EB dye and I2 / KI were 90.13% and 91.17%, respectively.

[0203] The results of option 2 are as follows Fig.11 (b) as shown:

[0204] The results were consistent with the trend that the removal rate of EB dye and I2 / KI decreased with the increase of ionic strength. At 1 g / L ionic concentration, the removal rate of PEI-P5-1 remained above 90%.

[0205] The results of option 3 are as follows Fig.11 (c) as shown:

[0206] It shows that the presence of humic acid will also affect the removal of EB dye and I2 / KI. When the concentration of humic acid is 1g / L, the removal rate of PEI-P5-1 is still above 90%. Therefore, the competitive adsorption between humic acid and anions is the main reason for the reduction of dye removal rate.

[0207] The result of option 4 is as follows Fig.11 (d) as shown:

[0208] PEI-P5-1 has the ability to effectively remove EB dye and I2 / KI in low-concentration solutions (50 ppb to 1 ppm), which indicates that PEI-P5-1 has the potential to achieve deep purification at low concentrations.

[0209] The above is only a preferred embodiment of the present invention, and the present invention is not limited to the above embodiments. It is understood that other improvements and changes directly derived or associated by those skilled in the art without departing from the spirit and concept of the present invention should be considered to be included in the protection scope of the present invention.

Claims

1. A method for preparing a supramolecular organic polymer, characterized in that: The preparation method comprises the following steps: (1) dissolving the brominated column [5] aromatic hydrocarbon in a solvent and adding polyethyleneimine to obtain a reactant, heating the reactant, and condensing and refluxing to obtain a mixed solution; (2) Cooling the mixed solution, filtering, washing, and drying to obtain the supramolecular organic polymer.

2. The preparation method according to claim 1, characterized in that: The polyethyleneimine is linear polyethyleneimine or branched polyethyleneimine, preferably branched polyethyleneimine; the molecular weight of the linear polyethyleneimine is in the range of 600-20000, preferably in the range of 10000-20000, and more preferably in the range of 20000.

3. The preparation method according to claim 1, characterized in that: In step (1), the molar ratio of the brominated column [5] aromatic hydrocarbon to polyethylene imine is (1-10):(1-10), preferably (1-5):(1-5), more preferably 1:(1-5), and more preferably 1:

1.

4. The preparation method according to claim 1, characterized in that: In step (1), the solvent includes one or more of anhydrous chloroform, dichloromethane, N,N-dimethylformamide, tetrahydrofuran, and methanol.

5. The preparation method according to claim 1, characterized in that: The method for preparing brominated column [5] aromatics comprises the following steps: (1) Preparation of brominated aromatic hydrocarbons: Add hydroquinone di(2-hydroxyethyl) ether to a solvent, and add triphenylphosphine and a catalyst thereto, react at 18-25°C for 2-6 hours, add water and shake after the reaction is completed, filter, rotary evaporate the filtrate, and dry to obtain a monomer; (2) Add the monomer obtained in step (1) to 1,2-dichloroethane, add polyformaldehyde and boron trifluoride ether thereto, and react at 18 to 25° C. for 1 to 3 hours. After the reaction is completed, extract, dry, filter, and rotary evaporate the filtrate to obtain crystals. After the crystals are dried, brominated column [5] aromatic hydrocarbons are obtained.

6. The supramolecular organic polymer obtained by the preparation method according to any one of claims 1 to 5.

7. Use of the supramolecular organic polymer according to claim 6 in adsorbing pollutants.

8. A method for adsorbing iodide ions, characterized in that: The method uses the supramolecular organic polymer described in claim 6.

9. A method for adsorbing Eosin B, characterized in that: The method uses the supramolecular organic polymer described in claim 6.

10. A method for improving the pollutant adsorption capacity of supramolecular organic polymers, comprising the following steps: (1) dissolving the brominated column [5] aromatic hydrocarbon in a solvent and adding polyethyleneimine to obtain a reactant, heating the reactant, and condensing and refluxing to obtain a mixed solution; (2) Cooling the mixed solution, filtering, washing, and drying to obtain the supramolecular organic polymer.

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