A phosphorus-oxygen functionalized hypercrosslinked porous polymer material and its preparation method and application

Abstract

The present invention discloses a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material, a preparation method and an application thereof, and belongs to the technical field of chemical adsorption materials. A method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material comprises the following steps: using tetraphenylmethane as a raw material, adding liquid bromine, and undergoing a substitution reaction to obtain brominated tetraphenylmethane; using diethyl phosphite and brominated tetraphenyltoluene as raw materials, under the action of a first catalyst, a catalytic reaction occurs to obtain phosphate-modified tetraphenylmethane; the phosphate-modified tetraphenylmethane is hydrolyzed in an acid solution to obtain a crude product of phosphate-modified tetraphenylmethane; and under a protective atmosphere, using 1,2-dichloroethane as a solvent, the crude product of phosphate-modified tetraphenylmethane and dimethoxymethane are subjected to an alkylation reaction under the action of a second catalyst to obtain a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material. The preparation method of the present invention is simple, and the prepared product has a good adsorption effect on uranium.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical adsorption materials, and more specifically to a phosphorus-oxygen functionalized super-crosslinked porous polymer material, a preparation method and an application thereof. Background Art

[0002] Against the backdrop of the gradual depletion of traditional energy resources, nuclear energy, as a new energy source, is garnering increasing attention and recognition. First, nuclear power generation provides clean, renewable energy, significantly reducing environmental pollution and helping to address environmental issues such as global warming and climate change. Second, compared with traditional fossil fuels, nuclear power generation does not emit significant amounts of greenhouse gases, effectively reducing carbon emissions and playing a significant role in mitigating global climate change. Nuclear energy reduces dependence on limited fossil energy sources and helps ensure long-term energy security. As the driving force behind nuclear energy, the secure and sustainable supply of uranium resources is crucial to the sustainable development of the nuclear energy industry and has a significant impact on the global economy.

[0003] However, the mining and processing of uranium resources can cause serious radioactive contamination. On the one hand, residual uranium is easily left during uranium mining, and some uranium-containing wastewater may seep into groundwater, causing groundwater contamination. On the other hand, the development of the nuclear industry produces uranium-containing waste and wastewater. If not properly handled, long-term accumulation can lead to the failure of environmental ecosystems, thereby affecting human drinking water safety and the health of the food chain.

[0004] In order to solve the problem of uranium-containing wastewater treatment, in recent years, researchers at home and abroad have mostly used metal-organic frameworks, aerogels, carbon nanotubes and other materials to adsorb uranium, and have achieved good experimental results. However, the former research materials still have defects, such as the difficulty of functional modification and poor adsorption selectivity, which greatly limits the application of these materials to a certain extent. Summary of the Invention

[0005] In response to the above problems, the present invention provides a phosphorus-oxygen functionalized hypercrosslinked porous polymer material, a preparation method, and an application. The hypercrosslinked polymers (HCPs) provided by the present invention are a low-density, high-specific surface area amorphous phosphorus-oxygen functionalized hypercrosslinked porous polymer material. The preparation method of the present invention is simple, and the prepared phosphorus-oxygen functionalized hypercrosslinked porous polymer material has a good adsorption effect on uranium.

[0006] The first object of the present invention is to provide a method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material, comprising the following steps:

[0007] Tetraphenylmethane is used as the raw material, liquid bromine is added, and a substitution reaction occurs to obtain tetraphenylmethane bromide.

[0008] Diethyl phosphite and tetraphenyltoluene bromide are used as raw materials, and a catalytic reaction occurs under the action of a first catalyst to obtain phosphate-modified tetraphenylmethane.

[0009] The phosphate-modified tetraphenylmethane is hydrolyzed in an acid solution to obtain a crude product of the phosphate-modified tetraphenylmethane.

[0010] Under a protective atmosphere, using 1,2-dichloroethane as a solvent, a crude product of phosphate-modified tetraphenylmethane as a raw material, and dimethoxymethane as a cross-linking agent, an alkylation reaction occurs under the action of a second catalyst to obtain a phosphorus-oxygen functionalized super-cross-linked porous polymer material.

[0011] In a preferred embodiment of the present invention, the molar ratio of tetraphenylmethane to liquid bromine is 1:4-5, for example, the molar ratio of tetraphenylmethane to liquid bromine is 1:4, 1:4.2, 1:4.4, 1:4.6, 1:4.8, 1:5, etc. It should be noted that liquid bromine is a volatile liquid. Therefore, in the actual preparation process, considering the easy volatility of liquid bromine, the amount of liquid bromine weighed is increased when measuring the liquid bromine to avoid the molar ratio of tetraphenylmethane to liquid bromine being less than 1:4-5 due to volatilization of liquid bromine during the reaction. For example, in the following Example 1, when the amount of tetraphenylmethane added is 0.811 g, the amount of liquid bromine added is increased to 20 mL.

[0012] The substitution reaction is carried out at room temperature under magnetic stirring for 5 to 6 hours. For example, magnetic stirring may be performed for 5 hours, 5.5 hours, 6 hours, etc. However, these values are not limited to the values listed above, and other values not listed within the above range are also applicable.

[0013] In a preferred embodiment of the present invention, the molar ratio of diethyl phosphite to tetraphenyltoluene bromide is 1 to 1.5:1, for example, the molar ratio of diethyl phosphite to tetraphenyltoluene bromide is 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, etc.

[0014] The molar ratio of tetraphenylmethane bromide to the first catalyst is 1:3.5-4, for example, the molar ratio of tetraphenylmethane bromide to the first catalyst is 1:3.5, 1:3.6, 1:3.7, 1:3.8, 1:3.9, 1:4, etc.

[0015] The catalytic reaction is carried out under magnetic stirring at 85°C to 90°C for 12h to 14h; the magnetic stirring temperature is 85°C, 86°C, 87°C, 88°C, 89°C, and 90°C, and the magnetic stirring time is 12h, 12.5h, 13h, 13.5h, 14h, etc., but is not limited to the listed values, and other values not listed within the above numerical range are also applicable.

[0016] The first catalyst is palladium hydroxide, ie Hirao palladium.

[0017] In a preferred embodiment of the present invention, the ratio of phosphate-modified tetraphenylmethane and acid solution is 3 g to 5 g: 20 mL, for example, the ratio of phosphate-modified tetraphenylmethane and acid solution is 3 g: 20 mL, 3.5 g: 20 mL, 4 g: 20 mL, 4.5 g: 20 mL, 5 g: 20 mL, etc.

[0018] The hydrolysis reaction is carried out at room temperature for 12 hours to 14 hours. For example, the hydrolysis time is 12 hours, 12.5 hours, 13 hours, 13.5 hours, 14 hours, etc., but is not limited to the listed values. Other values not listed within the above numerical range are also applicable.

[0019] In a preferred embodiment of the present invention, the molar ratio of the crude product of phosphate-modified tetraphenylmethane to dimethoxymethane is 1:16~20, for example, the molar ratio of the crude product of phosphate-modified tetraphenylmethane to dimethoxymethane is 1:16, 1:17, 1:18, 1:19, 1:20, etc.

[0020] The molar ratio of dimethoxymethane to anhydrous ferric chloride is 8 to 10:1. For example, the molar ratio of dimethoxymethane to anhydrous ferric chloride is 8:1, 8.5:1, 9:1, 9.5:1, 10:1, and the like.

[0021] The alkylation reaction is carried out at 80°C to 85°C for 20 to 24 hours. For example, the alkylation reaction temperature is 85°C, 86°C, 87°C, 88°C, 89°C, or 90°C, and the alkylation reaction time is 20 hours, 21 hours, 22 hours, 23 hours, or 24 hours, etc. However, these values are not limited to the above values, and other values not listed within the above range are also applicable.

[0022] In a preferred embodiment of the present invention, the second catalyst is anhydrous ferric chloride.

[0023] The second object of the present invention is to provide a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material prepared by the above preparation method.

[0024] The third object of the present invention is to provide the application of the above-mentioned phosphorus-oxygen functionalized hyper-crosslinked porous polymer material in wastewater treatment, which is characterized in that the phosphorus-oxygen functionalized hyper-crosslinked porous polymer material is added to uranium-containing wastewater for adsorption treatment.

[0025] In a preferred embodiment of the present invention, the uranium ion concentration in the uranium-containing wastewater is 1 ppm to 600 ppm. For example, the uranium ion concentration in the uranium-containing wastewater is 1 ppm, 100 ppm, 200 ppm, 300 ppm, 400 ppm, 500 ppm, 600 ppm, etc.

[0026] The pH of uranium-containing wastewater is 2~8, and the pH of uranium-containing wastewater is 2, 3, 4, 5, 6, 7, 8, etc.

[0027] The ratio of uranium-containing wastewater to phosphorus-oxygen functionalized hyper-cross-linked porous polymer material is 1 mL~4 mL:1 mg. For example, the ratio of uranium-containing wastewater to phosphorus-oxygen functionalized hyper-cross-linked porous polymer material is 1 mL:1 mg, 2 mL:1 mg, 3 mL:1 mg, 4 mL:1 mg, etc., but is not limited to the listed values. Other values not listed within the above numerical range are also applicable.

[0028] In a preferred embodiment of the present invention, the adsorption temperature is 25°C to 45°C, for example, the adsorption temperature is 25°C, 30°C, 35°C, 40°C, 45°C, etc.

[0029] The adsorption time is 5 minutes to 24 hours, for example, the adsorption time is 5 minutes, 1 hour, 3 hours, 9 hours, 15 hours, 20 hours, 24 hours, etc., but is not limited to the listed values. Other values not listed within the above numerical range are also applicable.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) The present invention uses tetraphenylmethane as a raw material to prepare phosphate-modified tetraphenylmethane. Phosphate-modified tetraphenylmethane is used as a reaction monomer and dimethoxymethane is used as a cross-linking agent. A phosphate-oxygen functionalized hypercross-linked porous polymer is synthesized in one step via a Friedel-Crafts alkylation reaction. The preparation method of the present invention has the advantages of being simple, easy to operate, and reusable.

[0032] The phosphorus-oxygen functionalized super-crosslinked porous polymer material adsorbent prepared by the present invention has a high adsorption capacity (adsorption capacity of 533.4 mg / g) for uranium ion-containing solutions and a fast adsorption speed, and can effectively adsorb and recover uranium ions in aqueous solutions.

[0033] (2) The phosphorus-oxygen functionalized super-cross-linked porous polymer material adsorbent prepared by the present invention has large specific surface area, high uranium adsorption capacity and short adsorption time. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the synthesis of phosphorus-oxygen functionalized hyper-cross-linked porous polymer material HCP-PL.

[0035] Figure 2 Characterization data of HCP-PL, where (a) is the XRD of HCP-PL and HCP-L; (b) is the scanning electron microscope image of HCP-L; (c) is the scanning electron microscope image of HCP-PL; (d) is the transmission electron microscope image of HCP-PL; and (e) is the surface energy spectrum of HCP-PL.

[0036] Figure 3 The infrared spectra and carbon NMR spectra of different samples are shown in Figure 2. (a) is the infrared spectra of HCP-PL and HCP-L; (b) is the infrared spectra of HCP-PL and HCP-L. 13 CNMR image.

[0037] Figure 4 N2 adsorption-desorption isotherms and pore size distribution diagrams of HCP-PL and HCP-L, where (a) is the N2 adsorption-desorption isotherm and (b) is the pore size distribution diagram.

[0038] Figure 5 The adsorption isotherms and fitting results of HCP-PL at 25℃~45℃, among which (a) is the adsorption isotherm of HCP-PL for uranium; (b) is the linear fitting experimental data diagram of the Langmuir isotherm model; (c) is the adsorption isotherm of HCP-L for uranium; (d) is the linear fitting experimental data diagram of the Langmuir isotherm model.

[0039] Figure 6 The adsorption capacity and fitting results of HCP-PL are shown, where (a) is the time-varying graph of the adsorption capacity of HCP-PL for uranium; (b) is the kinetic fitting graph of HCP-PL for uranium.

[0040] Figure 7 Graph showing the effect of pH on the adsorption performance of HCP-PL and HCP-L.

[0041] Figure 8 This is the recycling test result of HCP-PL. DETAILED DESCRIPTION

[0042] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0043] The present invention provides a method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material. The synthetic route is shown in Figure 1 , the specific preparation steps are as follows:

[0044] Tetraphenylmethane is used as the raw material, liquid bromine is added, and a substitution reaction occurs to obtain tetraphenylmethane bromide.

[0045] Diethyl phosphite and tetraphenyltoluene bromide are used as raw materials, and a catalytic reaction occurs under the action of a catalyst to obtain phosphate-modified tetraphenylmethane.

[0046] The phosphate-modified tetraphenylmethane is hydrolyzed in an acid solution to obtain a crude product of the phosphate-modified tetraphenylmethane.

[0047] Under protective atmosphere, 1,2-dichloroethane was used as solvent, the crude product of phosphorylated tetraphenylmethane was used as raw material, dimethoxymethane was used as cross-linking agent, and the phosphorus-oxygen functionalized hyper-crosslinked porous polymer HCP-PL was synthesized by Friedel-Crafts alkylation reaction in the presence of catalyst.

[0048] The present invention can easily control the pore structure and functional groups in the molecular skeleton by changing the type of cross-linking agent, the type of monomer involved in the synthesis, and the ratio of monomer to cross-linking agent, effectively making up for the shortcomings of the existing technology.

[0049] The hydrochloric acid used in the present invention is a hydrochloric acid solution with a concentration of 31%.

[0050] Example 1

[0051] This embodiment provides a method for preparing a phosphorus-oxygen functionalized hypercrosslinked porous polymer material. The synthetic route is as follows: Figure 1 The specific preparation method is as follows:

[0052] Step 1: Place 0.811 g of tetraphenylmethane in a three-necked flask, set up an exhaust gas treatment device, add 20 ml of liquid bromine to the three-necked flask, and stir at room temperature for 5 hours. Wash with NaHSO3 solution and deionized water, respectively, and then purify by column chromatography to obtain brominated tetraphenylmethane.

[0053] Step 2: 1.23 g of Hirao palladium, 3.464 g of diethyl phosphite, and 1.590 g of tetraphenylmethane bromide were catalyzed and reacted at 85° C. for 5 h to obtain phosphate-modified phosphate-functionalized tetraphenylmethane.

[0054] 20 ml of hydrochloric acid was added to 3 g of phosphate-modified phosphate-functionalized tetraphenylmethane, and the mixture was hydrolyzed at room temperature for 12 h to obtain a crude product of phosphate-modified tetraphenylmethane.

[0055] Step 3: Place 3.22 g (5 mmol) of the crude phosphate-modified tetraphenylmethane into a round-bottom flask containing 50 mL of 1,2-dichloroethane. Stir at room temperature for 1 hour. Then, under nitrogen, add 80 mmol of dimethoxymethane (FDA) and 10 mmol of anhydrous ferric chloride. The mixture is then reacted at 80°C for 24 hours. The crude product is collected by filtration and Soxhlet extracted with 100 mL of methanol at 80°C for 24 hours to remove residual catalyst and other substances within the pores. The product is then vacuum-dried at 60°C for 12 hours to yield a white powder solid, designated HCP-PL.

[0056] Example 2

[0057] This embodiment provides a method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material. The specific preparation method is as follows:

[0058] Step 1: Place 0.811 g of tetraphenylmethane in a three-necked flask, set up an exhaust gas treatment device, add 18 ml of liquid bromine to the three-necked flask, and stir at room temperature for 6 hours. Wash with NaHSO3 solution and deionized water, respectively, and then purify by column chromatography to obtain brominated tetraphenylmethane.

[0059] Step 2: 1.3 g of Hirao palladium, 5.18 g of diethyl phosphite, and 1.590 g of tetraphenylmethane bromide were catalyzed and reacted at 90° C. for 6 h to obtain phosphate-modified phosphate-functionalized tetraphenylmethane.

[0060] 20 ml of hydrochloric acid was added to 5 g of phosphate-modified phosphate-functionalized tetraphenylmethane, and the mixture was hydrolyzed at room temperature for 13 h to obtain a crude product of phosphate-modified tetraphenylmethane.

[0061] Step 3: Place 3.22 g (5 mmol) of the crude phosphate-modified tetraphenylmethane into a round-bottom flask containing 50 mL of 1,2-dichloroethane. Stir at room temperature for 1 hour. Then, under nitrogen, add 100 mmol of dimethoxymethane (FDA) and 10 mmol of anhydrous ferric chloride, followed by reaction at 82°C for 22 hours. Collect the crude product by filtration and perform Soxhlet extraction with 100 mL of methanol at 80°C for 24 hours to remove residual catalyst and other substances within the pores. The product is then vacuum-dried at 60°C for 12 hours to obtain a phosphine-oxygen-functionalized hypercrosslinked porous polymer.

[0062] Example 3

[0063] This embodiment provides a method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material. The specific preparation method is as follows:

[0064] Step 1: Place 0.811 g of tetraphenylmethane in a three-necked flask, set up an exhaust gas treatment device, add 19 ml of liquid bromine to the three-necked flask, and stir at room temperature for 5.5 hours. Wash with NaHSO3 solution and deionized water, respectively, and then purify by column chromatography to obtain brominated tetraphenylmethane.

[0065] Step 2: 1.4 g of Hirao palladium, 4.49 g of diethyl phosphite, and 1.590 g of tetraphenylmethane bromide were catalyzed and reacted at 87° C. for 5.5 h to obtain phosphate-modified phosphate-functionalized tetraphenylmethane.

[0066] 20 ml of hydrochloric acid was added to 4 g of phosphate-modified phosphate-functionalized tetraphenylmethane, and the mixture was hydrolyzed at room temperature for 14 h to obtain a crude product of phosphate-modified tetraphenylmethane.

[0067] Step 3: Place 3.22 g (5 mmol) of the crude phosphate-modified tetraphenylmethane into a round-bottom flask containing 50 mL of 1,2-dichloroethane. Stir at room temperature for 1 hour. Then, under nitrogen, add 90 mmol of dimethoxymethane (FDA) and 10 mmol of anhydrous ferric chloride, followed by reaction at 85°C for 20 hours. Collect the crude product by filtration and perform Soxhlet extraction with 100 mL of methanol at 80°C for 24 hours to remove residual catalyst and other substances within the pores of the material. The product is then vacuum-dried at 60°C for 12 hours to obtain a phosphine-oxygen-functionalized hypercrosslinked porous polymer material.

[0068] Comparative Example 1

[0069] This comparative example provides a method for preparing a non-functionalized tetraphenyl hyper-crosslinked porous polymer material. The specific preparation method is as follows:

[0070] Step 1. Place 1.6 g of tetraphenylmethane (5 mmol) in a round-bottom flask containing 50 mL of 1,2-dichloroethane. Stir at room temperature for 1 hour. Then, under nitrogen, add 80 mmol of dimethoxymethane (FDA) and 10 mmol of anhydrous ferric chloride. The mixture is then reacted at 80°C for 24 hours. The crude product is collected by filtration and Soxhlet extracted with 100 mL of methanol at 80°C for 24 hours to remove residual catalyst and other substances within the pores. The product is then vacuum-dried at 60°C for 12 hours to yield a white powdery solid, designated HCP-L.

[0071] from Figure 2 As can be seen from (a), the XRD patterns of HCP-L and HCP-PL show obvious amorphous structures. Figure 2 As can be seen from (b), the surface morphology of HCP-L and HCP-PL has not changed much, and the phosphorus oxidation process does not significantly change the morphology of the material. The morphology and composition of HCP-PL were studied by SEM, TEM and EDS. Figure 2 As shown in (c), HCP-PL consists of irregular rod-like structures. Figure 2 The HR-TEM image in (d) further confirms the SEM results that HCP-PL has amorphous micropores. Figure 2 As can be seen from (e), the phosphorus oxygen groups in HCP-PL are abundant and evenly dispersed, which is very helpful for the adsorption of uranium.

[0072] Fourier transform infrared spectroscopy (FT-IR) and solid-state 13The structures of HCP-L and HCP-PL were characterized by C NMR. Figure 3 As shown in (a), the Fourier transform infrared spectrum of HCP-L is compared with that of HCP-PL. -1 The characteristic band of P=O is shown at 1008 cm -1 The characteristic band of P-OH is shown at 13 CNMR also confirmed the success of cross-linking. Figure 3 As shown in (b), the chemical shift at 150 ppm can be attributed to CP and C5. The chemical shift at 45 ppm can be attributed to the -CH2- carbon C7. The chemical shifts C = 125 ppm and 65 ppm can be attributed to aromatic carbons C3, C4, C6 and trivalent hydrocarbon carbon C1, respectively, further indicating that the monomers were successfully cross-linked under the action of the catalyst.

[0073] The properties of the material were further determined by BET analysis. The surface area of the material was determined by N2 adsorption-desorption isotherms. At low pressures (P / P0 < 0.1), nitrogen increased rapidly, indicating the presence of a large number of micropores. A hysteresis loop existed in the pressure region of P / P0 = 0.2 to 0.8, indicating that this region had certain mesoporous characteristics. When the relative pressure was greater than 0.8, the hysteresis loop indicated the presence of macropores and mesopores. The grafting of phosphorus oxide groups resulted in a BET specific surface area of 665.3 m2 / s of HCP-L. 2 / g decreased to 108.6 m 2 / g. Although the specific surface area of HCP-PL is reduced, the introduction of a large number of phosphorus oxygen groups has greatly increased the P content to 10.36%. The introduction of phosphorus oxygen groups greatly improves the adsorption performance of the material, enabling HCP-PL to contact and interact with uranyl ions more quickly. According to the non-local density functional theory (NL-DFT) method, the average pore sizes of HCP-L and HCP-PL are 2.5 nm and 9.78 nm, respectively. The adsorption material is mainly mesoporous, and a large number of mesopores are conducive to the adsorption of uranium. Figure 4 .

[0074] The experimental method for adsorbing, separating and enriching uranium ions using a phosphorus-oxygen functionalized hypercrosslinked porous polymer material comprises the following steps:

[0075] (1) A series of uranium solutions with different concentrations ranging from 1 to 600 ppm were prepared for adsorption experiments. 5 ± 0.2 mg of phosphorus-oxygen functionalized hypercrosslinked porous polymer material (HCP-PL) was added to 5 mL of uranium aqueous solution and continuously shaken at room temperature for 24 h. The adsorbed HCP-PL was separated from the solution using a disposable filter device, and the filtrate concentration was characterized by UV-visible spectroscopy at a wavelength of 618 nm. The adsorption capacity of HCP-PL for uranium and its removal rate were calculated as follows:

[0076]

[0077]

[0078] in, q e is the adsorption capacity when adsorption reaches equilibrium (mg / g); C o is the initial concentration of uranyl nitrate hexahydrate solution before adsorption; C e is the equilibrium concentration of uranyl nitrate hexahydrate solution after adsorption; V is the volume of uranyl nitrate hexahydrate solution in the experiment (mL); m is the mass of HCP-PL adsorbent (mg); R is the removal rate of uranyl ions.

[0079] (2) For the kinetic adsorption study, HCP-PL was subjected to two concentrations of uranyl nitrate solution (60 mg / L and 80 mg / L) at a pH of 6. Several glass bottles were added with 10 mL of uranyl nitrate solution and 5 mg of HCP-PL, respectively. The bottles were placed in an oscillator at 25°C and oscillated for different time periods at regular intervals. The adsorbed HCP-PL was separated from the solution using a disposable filter device, and the filtrate concentration was tested using UV-visible spectroscopy. As a control group, the kinetic data of the unmodified HCP-L polymer material was tested at a uranyl nitrate solution of 60 mg / L, and the test method was consistent with the above.

[0080] (3) To study the effect of pH on adsorption performance, the pH of the uranyl nitrate hexahydrate solution was adjusted by acid-base titration using 0.1 M nitric acid and 0.1 M sodium hydroxide solution. The pH environment was adjusted to 1.5, 2, 3, 4, 5, and 6. 5 mg of HCP-PL and HCP-L adsorbents were weighed in sequence at room temperature and added to 10 mL of 60 mg / L uranyl nitrate hexahydrate solution. After adding 10 mL of each of the adsorbents to 10 mL of 60 mg / L uranyl nitrate hexahydrate solution, the adsorption was allowed to proceed on a mechanical shaker at 25°C for 12 h. After the adsorption was completed, the uranium concentration was measured using a UV-visible spectrophotometer.

[0081] (4) For the cyclic adsorption study, 25 mg of HCP-PL adsorbent was added to 100 mL of uranyl nitrate hexahydrate solution with a concentration of 100 mg / L and adsorbed on a mechanical shaker at 25°C for 2 h. After the adsorption was completed, the HCP-PL adsorbent and uranyl nitrate hexahydrate solution were separated using a high-speed centrifuge. The supernatant was taken and the uranyl ion concentration was measured using a UV-visible spectrophotometer to calculate the HCP-PL removal rate. After solid-liquid separation, the adsorbed material was desorbed with 2 M nitric acid, washed with deionized water, and vacuum dried at 80°C. The above experimental steps were repeated 5 times, and the reproducible performance of HCP-PL after 5 adsorption-desorption cycles was studied. In order to reduce the error caused by the experiment, three parallel experiments were performed on all experimental samples.

[0082] In the present invention, the ultraviolet-visible absorption spectrum (UV-Vis) is measured using a Beijing Puxi General Instrument T6 New Century UV-visible spectrometer.

[0083] See the following examples for details.

[0084] Example 4

[0085] Eleven different uranyl nitrate solution concentration gradients were established. The concentrations of the uranyl nitrate solutions were 1 mg / L, 5 mg / L, 10 mg / L, 20 mg / L, 60 mg / L, 100 mg / L, 200 mg / L, 300 mg / L, 400 mg / L, 500 mg / L, and 600 mg / L, respectively. 10 mL of each uranyl nitrate solution was pipetted into a glass vial, and 5 mg of HCP-PL and HCP-L were added. The vial was then shaken at 25°C for 4 h. After shaking, 1 mL of the solution was pipetted through a filter into a 25 mL volumetric flask using a 1 mL syringe. 2 mL of arsenazo III and 2 mL of sodium chloroacetate buffer were added to the volume. The solution was shaken until well mixed, and the absorbance of the different solutions was measured at 652 nm using a UV-visible spectrometer. The absorbance of the solutions at different temperatures was recorded. The adsorption isotherms of HCP-PL and HCP-L were plotted using the experimental data from the adsorption isotherm experiment. The adsorption isotherms of HCP-PL and HCP-L were then fitted using the Freundlich model and the Langmuir model. The results showed that HCP-L and HCP-PL were more consistent with the Langmuir model. The linear correlation coefficient of HCP-PL fitting to uranyl nitrate solution R 2 As high as 0.995 or above, see Figure 5 .

[0086] Example 5

[0087] For the modified HCP-PL, two concentrations of uranyl nitrate solution with a pH of 6, 60 mg / L and 80 mg / L, were used, respectively. Several glass bottles were added with 10 mL of uranyl nitrate solution and 5 mg of HCP-PL, respectively. The bottles were placed in an oscillator at 25°C and shaken for 5, 10, 20, 30, 50, 80, 110, 150, 240, and 360 min, respectively. 1 mL of the shaken solution was aspirated with a syringe and filtered through a water filter. The solution was then added to a 25 mL volumetric flask, and 2 mL of arsenazo III and 2 mL of buffer were added to the volume. The solution was shaken until uniformly mixed, and the absorbance of the filtrate was measured at 652 nm by UV-visible spectroscopy, and the experimental data were recorded. For the unmodified HCP-L polymer material, the kinetic data at 60 mg / L uranyl nitrate solution was tested as a control group, and the test method was consistent with the above.

[0088] The experimental data of HCP-PL and HCP-L were fitted using the quasi-first and quasi-second-order kinetic models commonly used in adsorption studies to explore the adsorption mechanism of HCP-PL and HCP-L. HCP-PL has a high adsorption performance for uranium, which conforms to the quasi-second-order kinetic model. Under the conditions of initial concentrations of 60 mg / L and 80 mg / L and a solid-liquid ratio of 1:2, the adsorption equilibrium time of HCP-PL was 180 min and 240 min, respectively. The adsorption rate of HCP-PL is relatively fast, which is the result of the complexation of phosphorus oxygen groups with U (VI), such as Figure 6 As shown in (a).

[0089] In order to study the adsorption kinetics of uranium on HCP-PL, pseudo-first-order kinetic model and pseudo-second-order kinetic model were used for data analysis. The fitting results showed that HCP-PL conforms to the pseudo-second-order kinetic model. After fitting the experimental data with the pseudo-second-order kinetic model, the linear correlation coefficient R 2 The calculated adsorption rate constant is 0.987. k The value of 2 is 8.19×10 -4 g·mg·min -1 The results show that the adsorption of uranium ions by HCP-PL follows pseudo-second-order kinetics. The maximum theoretical uranium adsorption capacity of HCP-PL is very close to the experimental value. Figure 6 (b).

[0090] Example 6

[0091] The adsorption performance of HCP-PL and HCP-L for uranyl ions was studied at various pH values. The pH of the uranyl nitrate hexahydrate solution was adjusted by acid-base titration with 0.1 M nitric acid and 0.1 M sodium hydroxide solution. The pH range was adjusted to 2, 3, 4, 5, 6, 7, and 8. At room temperature, 5 mg of HCP-PL and HCP-L adsorbents were weighed and added to 10 mL glass vials. Then, 10 mL of 60 mg / L uranyl nitrate hexahydrate solution was added to each vial. The adsorption was allowed to proceed on a mechanical shaker set at 25°C for 12 hours. After adsorption, the uranium concentration was measured using a UV-visible spectrophotometer. Figure 7 The results show that with the increase of pH value, the adsorption amount shows a trend of first increasing and then decreasing. When the pH value increases to about 6, the adsorption amount of uranium by the adsorbate basically reaches equilibrium.

[0092] Example 7

[0093] 25 mg of HCP-PL adsorbent was added to 50 mL of uranyl nitrate hexahydrate solution at a concentration of 100 mg / L. The adsorption process was carried out on a mechanical shaker at 25°C for 2 h. After adsorption, the HCP-PL adsorbent and uranyl nitrate hexahydrate solution were separated using a high-speed centrifuge. The supernatant was collected and the uranyl ion concentration was measured using a UV-visible spectrophotometer to calculate the HCP-PL removal rate. After solid-liquid separation, the adsorbed material was desorbed with 2 M nitric acid, washed with deionized water, and dried under vacuum at 80°C. The experimental steps were repeated five times, and the reproducible performance of the HCP-PL after five adsorption-desorption cycles was investigated. To reduce experimental error, triplicate experiments were performed for all samples. After five adsorption-desorption cycles, the HCP-PL maintained a removal percentage exceeding 80%. Figure 8 The results showed that the material has good reusability and can effectively remove dyes from aqueous solutions.

[0094] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0095] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material, characterized in that: The following steps are involved: Tetraphenylmethane is used as the raw material, and liquid bromine is added to cause a substitution reaction to obtain tetraphenylmethane bromide; Using diethyl phosphite and tetraphenylmethane bromide as raw materials, a catalytic reaction occurs under the action of a first catalyst to obtain phosphate-modified tetraphenylmethane; The phosphate-modified tetraphenylmethane is hydrolyzed in an acid solution to obtain a crude product of the phosphate-modified tetraphenylmethane; Under a protective atmosphere, using 1,2-dichloroethane as a solvent, a crude product of phosphate-modified tetraphenylmethane as a raw material, and dimethoxymethane as a cross-linking agent, an alkylation reaction occurs under the action of a second catalyst to obtain a phosphorus-oxygen functionalized super-cross-linked porous polymer material.

2. The method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material according to claim 1, characterized in that: The molar ratio of tetraphenylmethane to liquid bromine is 1:4~5, and the substitution reaction is carried out at room temperature under magnetic stirring for 5h~6h.

3. The method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material according to claim 1, characterized in that: The molar ratio of diethyl phosphite to tetraphenylmethane bromide is 10-15:1, the molar ratio of tetraphenylmethane bromide to the first catalyst is 1:3.5-4, and the catalytic reaction is carried out at 85-90° C. with magnetic stirring for 5-6 hours.

4. The method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material according to claim 1, characterized in that: The ratio of phosphate-modified tetraphenylmethane to acid solution is 3 g~5 g:20 mL, and the hydrolysis reaction is carried out at room temperature for 12 h~14 h.

5. The method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material according to claim 1, characterized in that: The molar ratio of the crude product of phosphate-modified tetraphenylmethane to dimethoxymethane is 1:16-20, the molar ratio of dimethoxymethane to the second catalyst is 8-10:1, and the alkylation reaction is carried out at 80°C-85°C for 20h-24h.

6. The method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material according to claim 1, characterized in that: The first catalyst is palladium hydroxide, and the second catalyst is anhydrous ferric chloride.

7. A phosphorus-oxygen functionalized hyper-crosslinked porous polymer material prepared by the preparation method according to any one of claims 1 to 6.

8. Use of the phosphorus-oxygen functionalized hyper-crosslinked porous polymer material according to claim 7 in wastewater treatment, characterized in that: Phosphorus-oxygen functionalized hyper-cross-linked porous polymer materials are added to uranium-containing wastewater for adsorption treatment.

9. The use of a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material in wastewater treatment according to claim 8, characterized in that: The uranium ion concentration in the uranium-containing wastewater is 1ppm~600ppm, the pH of the uranium-containing wastewater is 2~8, and the ratio of uranium-containing wastewater to phosphorus-oxygen functionalized hyper-cross-linked porous polymer material is 2mL:1mg.

10. The use of a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material in wastewater treatment according to claim 8, characterized in that: The adsorption temperature is 25℃~45℃, and the adsorption time is 5min~24h.

Images