Phosphorus-oxygen functionalized super-crosslinked porous polymer material as well as preparation method and application thereof

Abstract

The invention discloses a phosphorus-oxygen functionalized super-crosslinked porous polymer material as well as a preparation method and application thereof, and belongs to the technical field of chemical adsorption materials. The invention relates to a preparation method of a phosphorus-oxygen functionalized super-crosslinked porous polymer material, which comprises the following steps: adding liquid bromine into tetraphenylmethane serving as a raw material, and carrying out substitution reaction to obtain tetraphenylmethane bromide; the preparation method comprises the following steps: by taking diethyl phosphite and brominated tetraphenyltoluene as raw materials, carrying out catalytic reaction under the action of a first catalyst to obtain phosphate modified tetraphenylmethane; carrying out hydrolysis treatment on the phosphate modified tetraphenylmethane in an acid solution to obtain a crude product of the phosphate modified tetraphenylmethane; 1, 2-dichloroethane is used as a solvent in a protective atmosphere, and the crude product of phosphate modified tetraphenylmethane and dimethoxymethane are subjected to an alkylation reaction under the action of a second catalyst to obtain the phosphorus-oxygen functionalized super-crosslinked porous polymer material. The preparation method is simple, and the prepared product has a good uranium adsorption effect.

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 and a preparation method and application thereof. Background Art

[0002] As the driving force of nuclear energy, the secure and sustainable supply of uranium resources is crucial to the sustainable development of the nuclear energy industry.

[0003] However, the mining and processing of uranium resources can cause radioactive pollution. On the one hand, residual uranium is likely to appear during the mining process, and some uranium-containing wastewater may seep into groundwater, causing groundwater pollution; on the other hand, uranium-containing waste and wastewater are generated during the development of the nuclear industry. If not properly handled, long-term accumulation may lead to the failure of the environmental ecosystem.

[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 view of the above problems, the present invention provides a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material, a preparation method and an application thereof. The hyper-crosslinked polymers (Hypercrosslinked polymers, HCPs) provided by the present invention are a low-density, high-specific surface area amorphous phosphorus-oxygen functionalized hyper-crosslinked porous polymer material. The preparation method of the present invention is simple, and the prepared phosphorus-oxygen functionalized hyper-crosslinked 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: Take tetraphenylmethane as the raw material, add liquid bromine, and a substitution reaction occurs to obtain tetraphenylmethane bromide.

[0007] 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.

[0008] The phosphate-modified tetraphenylmethane is hydrolyzed in an acid solution to obtain a crude product of the phosphate-modified tetraphenylmethane.

[0009] Under a protective atmosphere, 1,2-dichloroethane is used as a solvent, a crude product of phosphate-modified tetraphenylmethane is used as a raw material, and dimethoxymethane is used as a cross-linking agent. Under the action of a second catalyst, an alkylation reaction occurs to obtain a phosphorus-oxygen functionalized super-cross-linked porous polymer material.

[0010] 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 problem that liquid bromine is easy to volatilize, the amount of liquid bromine weighed will be increased when measuring liquid bromine to avoid the molar ratio of tetraphenylmethane to liquid bromine being less than 1:4-5 due to the 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.

[0011] The substitution reaction is carried out under magnetic stirring at room temperature for 5 to 6 hours, for example, under magnetic stirring for 5 hours, 5.5 hours, 6 hours, etc., but the values ​​listed are not limited thereto, and other values ​​not listed within the above range are also applicable.

[0012] In a preferred embodiment of the present invention, the molar ratio of diethyl phosphite to tetraphenyltoluene bromide is 1-1.5:1, 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.

[0013] 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.

[0014] The catalytic reaction is carried out under magnetic stirring at 85°C ~ 90°C for 12h ~ 14h; the temperature of magnetic stirring is 85°C, 86°C, 87°C, 88°C, 89°C, 90°C, and the time of magnetic stirring 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.

[0015] The first catalyst is palladium hydroxide, ie Hirao palladium.

[0016] In a preferred embodiment of the present invention, the ratio of phosphate-modified tetraphenylmethane and acid solution is 3g~5g:20mL, for example, the ratio of phosphate-modified tetraphenylmethane and acid solution is 3g:20mL, 3.5g:20mL, 4g:20mL, 4.5g:20mL, 5g:20mL, etc.

[0017] The hydrolysis reaction is carried out at room temperature for 12 h to 14 h. For example, the hydrolysis time is 12 h, 12.5 h, 13 h, 13.5 h, 14 h, etc., but is not limited to the listed values. Other values ​​not listed within the above numerical range are also applicable.

[0018] 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.

[0019] 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.

[0020] The alkylation reaction is carried out at 80°C to 85°C for 20h to 24h. For example, the temperature of the alkylation reaction is 85°C, 86°C, 87°C, 88°C, 89°C, 90°C, and the time of the alkylation reaction is 20h, 21h, 22h, 23h, 24h, etc., but it is not limited to the listed values, and other values ​​not listed in the above numerical range are also applicable.

[0021] In a preferred embodiment of the present invention, the second catalyst is anhydrous ferric chloride.

[0022] The second object of the present invention is to provide a phosphorus-oxygen functionalized super-crosslinked porous polymer material prepared by the above preparation method.

[0023] 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, characterized in that the phosphorus-oxygen functionalized hyper-crosslinked porous polymer material is added to the uranium-containing wastewater for adsorption treatment.

[0024] 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.

[0025] The pH value of uranium-containing wastewater is 2~8, and the pH value of uranium-containing wastewater is 2, 3, 4, 5, 6, 7, 8, etc.

[0026] The ratio of uranium-containing wastewater to phosphorus-oxygen functionalized hyper-crosslinked porous polymer material is 1mL~4mL:1mg. For example, the ratio of uranium-containing wastewater to phosphorus-oxygen functionalized hyper-crosslinked porous polymer material is 1mL:1mg, 2mL:1mg, 3mL:1mg, 4mL:1mg, etc., but is not limited to the listed values, and other unlisted values ​​within the above numerical range are also applicable.

[0027] 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.

[0028] The adsorption time is 5 min to 24 h, for example, the adsorption time is 5 min, 1 h, 3 h, 9 h, 15 h, 20 h, 24 h, etc., but is not limited to the listed values, and other unlisted values ​​within the above numerical range are also applicable.

[0029] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention uses tetraphenylmethane as a raw material to prepare phosphate-modified tetraphenylmethane, uses phosphate-modified tetraphenylmethane as a reaction monomer, and uses dimethoxymethane as a crosslinking agent to synthesize a phosphorus-oxygen functionalized super-crosslinked porous polymer in one step through a Friedel-Crafts alkylation reaction. The preparation method of the present invention has the advantages of being simple, easy to operate, and reusable.

[0030] 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.

[0031] (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

[0032] Figure 1 Schematic diagram of the synthesis of phosphorus-oxygen functionalized hyper-cross-linked porous polymer material HCP-PL.

[0033] Figure 2 Characterization data of HCP-PL, where (a) is the XRD of HCP-PL and HCP-L; (b) is the SEM image of HCP-L; (c) is the SEM image of HCP-PL; (d) is the TEM image of HCP-PL; (e) is the surface energy spectrum of HCP-PL.

[0034] Figure 3Infrared spectra and carbon NMR spectra of different samples, where (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.

[0035] Figure 4 N of HCP-PL and HCP-L 2 Adsorption-desorption isotherms and pore size distribution diagram, where (a) is N 2 Adsorption-desorption isotherm, (b) pore size distribution diagram.

[0036] 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.

[0037] Figure 6 The adsorption capacity and fitting results of HCP-PL, 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.

[0038] Figure 7 This is the effect of pH value on the adsorption performance of HCP-PL and HCP-L.

[0039] Figure 8 This is a graph showing the recycling test results of HCP-PL. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0041] 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: Take tetraphenylmethane as the raw material, add liquid bromine, and a substitution reaction occurs to obtain tetraphenylmethane bromide.

[0042] With diethyl phosphite and tetraphenyltoluene bromide as raw materials, a catalytic reaction occurs under the action of a catalyst to obtain phosphate-modified tetraphenylmethane.

[0043] The phosphate-modified tetraphenylmethane is hydrolyzed in an acid solution to obtain a crude product of the phosphate-modified tetraphenylmethane.

[0044] Phosphorus-oxygen functionalized hyper-crosslinked porous polymer HCP-PL was synthesized by Friedel-Crafts alkylation reaction under protective atmosphere with 1,2-dichloroethane as solvent, crude product of phosphorylated functionalized tetraphenylmethane as raw material and dimethoxymethane as crosslinking agent.

[0045] The present invention can easily control the pore structure and the 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 the monomer to the cross-linking agent, thereby effectively making up for the shortcomings of the prior art.

[0046] The hydrochloric acid used in the present invention is a hydrochloric acid solution with a concentration of 31%.

[0047] Example 1 This embodiment provides a method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material. The synthesis route is as follows: Figure 1 The specific preparation method is as follows: 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 h. 3 The solution was washed with deionized water and then purified by column chromatography to obtain tetraphenylmethane bromide.

[0048] Step 2: 1.23 g of Hirao palladium, 3.464 g of diethyl phosphite and 1.590 g of tetraphenylmethane bromide were catalytically reacted at 85° C. for 5 h to obtain phosphate-modified phosphate-functionalized tetraphenylmethane.

[0049] 20 ml of hydrochloric acid was added to 3 g of phosphate-modified phosphate-functionalized tetraphenylmethane, and hydrolyzed at room temperature for 12 h to obtain a crude product of phosphate-modified tetraphenylmethane.

[0050] Step 3: Place 3.22 g and 5 mmol of the crude product of phosphate-modified tetraphenylmethane into a round-bottom flask filled with 50 mL of 1,2-dichloroethane. Stir at room temperature for 1 h, then add 80 mmol of dimethoxymethane (Formaldehyde dimethyl acetal, FDA) and 10 mmol of anhydrous ferric chloride in sequence under nitrogen, and then react at 80 ° C for 24 h. Collect the crude product by filtration, then perform Soxhlet extraction with 100 mL of methanol at 80 ° C for 24 h to remove the residual catalyst and other substances in the pores of the material, and vacuum dry at 60 ° C for 12 h to obtain a white powder solid, which is recorded as HCP-PL.

[0051] Example 2 This embodiment provides a method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material. The specific preparation method is as follows: 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 h. 3 The solution was washed with deionized water and then purified by column chromatography to obtain tetraphenylmethane bromide.

[0052] Step 2: 1.3 g of Hirao palladium, 5.18 g of diethyl phosphite and 1.590 g of tetraphenylmethane bromide were catalyzed at 90° C. for 6 h to obtain phosphate-modified phosphate-functionalized tetraphenylmethane.

[0053] 20 ml of hydrochloric acid was added to 5 g of phosphate-modified phosphate-functionalized tetraphenylmethane, and hydrolyzed at room temperature for 13 h to obtain a crude product of phosphate-modified tetraphenylmethane.

[0054] Step 3: Place 3.22 g and 5 mmol of the crude product of phosphate-modified tetraphenylmethane into a round-bottom flask containing 50 mL of 1,2-dichloroethane. Stir at room temperature for 1 h, then add 100 mmol of dimethoxymethane (FDA) and 10 mmol of anhydrous ferric chloride in sequence under nitrogen, and then react at 82 °C for 22 h. Collect the crude product by filtration, then perform Soxhlet extraction with 100 mL of methanol at 80 °C for 24 h to remove the residual catalyst and other substances in the pores of the material, and vacuum dry at 60 °C for 12 h to obtain a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material.

[0055] Example 3 This embodiment provides a method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material. The specific preparation method is as follows: 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 h. 3 The solution was washed with deionized water and then purified by column chromatography to obtain tetraphenylmethane bromide.

[0056] 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.

[0057] 20 ml of hydrochloric acid was added to 4 g of phosphate-modified phosphate-functionalized tetraphenylmethane, and hydrolyzed at room temperature for 14 h to obtain a crude product of phosphate-modified tetraphenylmethane.

[0058] Step 3: Place 3.22 g and 5 mmol of the crude product of phosphate-modified tetraphenylmethane into a round-bottom flask containing 50 mL of 1,2-dichloroethane. Stir at room temperature for 1 h, then add 90 mmol of dimethoxymethane (FDA) and 10 mmol of anhydrous ferric chloride in sequence under nitrogen, and then react at 85 ° C for 20 h. Collect the crude product by filtration, then perform Soxhlet extraction with 100 mL of methanol at 80 ° C for 24 h to remove the residual catalyst and other substances in the pores of the material, and vacuum dry at 60 ° C for 12 h to obtain a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material.

[0059] Comparative Example 1 This comparative example provides a method for preparing a non-functionalized tetraphenyl hyper-crosslinked porous polymer material, and the specific preparation method is as follows: Step 1. Place 1.6 g and 5 mmol of tetraphenylmethane in a round-bottom flask containing 50 mL of 1,2-dichloroethane. Stir at room temperature for 1 h, then add 80 mmol of dimethoxymethane (FDA) and 10 mmol of anhydrous ferric chloride in sequence under nitrogen, and then react at 80 ° C for 24 h. Collect the crude product by filtration, then perform Soxhlet extraction with 100 mL of methanol at 80 ° C for 24 h to remove the residual catalyst and other substances in the pores of the material, and vacuum dry at 60 ° C for 12 h to obtain a white powder solid, recorded as HCP-L.

[0060] from Figure 2 As can be seen from (a) in Figure 2, the XRD patterns of HCP-L and HCP-PL show obvious amorphous structures. Figure 2 As can be seen from (b) in the figure, 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 is composed 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.

[0061] Fourier transform infrared spectroscopy (FT-IR) and solid state 13 The 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. -1The 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 -CH 2 -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, which further indicates that the monomers are successfully cross-linked under the action of the catalyst.

[0062] The properties of the material were further determined by BET analysis. 2 The adsorption-desorption isotherm determines the surface area of ​​the material. 0 <0.1), nitrogen increases rapidly, indicating the presence of a large number of micropores. 0 = 0.2~0.8, indicating that this region has certain mesoporous characteristics. When the relative pressure is greater than 0.8, the hysteresis loop indicates the presence of macropores and mesopores. The grafting of phosphine groups leads to 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, a large number of phosphorus oxygen groups are introduced, and the P content is greatly increased to 10.36%. The introduction of phosphorus oxygen groups greatly improves the adsorption performance of the material, allowing HCP-PL to contact and interact with uranyl ions faster. 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 mesopores, and a large number of mesopores are conducive to the adsorption of uranium, see Figure 4 .

[0063] The experimental method for adsorbing, separating and enriching uranium ions by phosphorus-oxygen functionalized hyper-crosslinked porous polymer materials comprises the following steps: (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 filtration device, and the concentration of the filtrate 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: in,q e is the adsorption capacity when the 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.

[0064] (2) For the kinetic adsorption study, HCP-PL was subjected to uranyl nitrate solution with a pH of 6 at two concentrations, 60 mg / L and 80 mg / L, 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 oscillated for different time periods at regular intervals. The adsorbed HCP-PL was separated from the solution using a disposable filtration device, and the filtrate concentration was tested using UV-visible spectroscopy. As 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.

[0065] (3) For the study of the effect of pH on adsorption performance, the pH of the hexahydrate uranyl nitrate solution was adjusted by acid-base titration using 0.1M nitric acid and 0.1M 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 turn at room temperature and added to 10 mL of a 10 mL glass sample bottle. After adding 10 mL of 60 mg / L hexahydrate uranyl nitrate solution to each of them, the adsorbents were shaken and adsorbed on a mechanical shaker at an internal environment of 25°C for 12 h. After the adsorption was completed, the uranium concentration was measured using a UV-visible spectrophotometer.

[0066] (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, the HCP-PL adsorbent and uranyl nitrate hexahydrate solution were separated by a high-speed centrifuge. The upper clear liquid was taken and the uranyl ion concentration was measured by UV-visible spectrophotometer to calculate the removal rate of HCP-PL. 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 repeatable 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 carried out on all experimental samples.

[0067] The ultraviolet-visible absorption spectrum (UV-Vis) in the present invention is measured using a Beijing Puxi General Instrument T6 New Century Ultraviolet Visible Spectrometer.

[0068] See the following examples for details.

[0069] Example 4 Eleven different concentration gradients of uranyl nitrate solution were set. The concentrations of uranyl nitrate solution 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 uranyl nitrate solution of different concentrations was drawn into a glass bottle with a pipette, and 5 mg of HCP-PL and HCP-L were added respectively. Then it was placed in an oscillator and oscillated at 25 °C for 4 h. After the oscillation was completed, 1 mL of solution was drawn into a 25 mL volumetric flask through the filter head with a 1 mL syringe, and then 2 mL of azoarsine III and 2 mL of sodium chloroacetate acetate buffer were added to the volume. The solution was shaken until mixed evenly, and finally measured by UV-visible spectrometer at 652 nm light, and the absorbance of different solutions was recorded. The absorbance of the solution at different temperatures was recorded. The adsorption isotherms of HCP-PL and HCP-L were drawn based on the experimental data measured by the adsorption isotherm experiment, and then the adsorption isotherms of HCP-PL and HCP-L were fitted by 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, see Figure 5 .

[0070] Example 5 For the modified HCP-PL, two concentrations of uranyl nitrate solution of 60 mg / L and 80 mg / L, pH 6 were used. Several glass bottles were taken, 10 mL of uranyl nitrate solution and 5 mg HCP-PL were added respectively, and the bottles were placed in an oscillator at 25°C for 5, 10, 20, 30, 50, 80, 110, 150, 240, and 360 min respectively. After the solution was shaken, 1 mL was drawn with a syringe and filtered through a water filter. It was then added to a 25 mL volumetric flask, and 2 mL of azoarsine III and 2 mL of buffer were added to make up the volume. The solution was shaken until mixed evenly 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 when the uranyl nitrate solution was 60 mg / L was tested as the control group, and the test method was consistent with the above.

[0071] The quasi-first and quasi-second-order kinetic models commonly used in adsorption research were used to fit the experimental data of HCP-PL and HCP-L 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 (a) shown.

[0072] 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 conformed 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 is 0.987, and the calculated adsorption rate constant k 2 The value is 8.19×10 -4 g·mg·min -1 The results show that the adsorption of uranium ions by HCP-PL conforms to pseudo-second-order kinetics. The maximum theoretical uranium adsorption capacity of HCP-PL is very close to the experimental value. Figure 6 (b).

[0073] Example 6 The adsorption performance of HCP-PL and HCP-L on uranyl ions was studied at different pH values. The pH of 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 environment was adjusted to 2, 3, 4, 5, 6, 7, and 8. 5 mg of HCP-PL and HCP-L adsorbents were weighed in turn at room temperature and added to 10 mL glass sample bottles. Then 10 mL of 60 mg / L uranyl nitrate hexahydrate solution was added respectively, and the adsorption was shaken on a mechanical shaker for 12 h, and the environment in the shaker was set to 25°C. After the adsorption was completed, the concentration of uranium 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.

[0074] Example 7 25 mg of HCP-PL adsorbent was added to 50 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, the HCP-PL adsorbent and uranyl nitrate hexahydrate solution were separated by a high-speed centrifuge. The supernatant was taken, and the uranyl ion concentration was measured by UV-visible spectrophotometer to calculate the removal rate of HCP-PL. 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 repeatable 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 carried out for all experimental samples. After 5 adsorption-desorption cycle experiments, HCP-PL was still able to maintain a removal percentage of more than 80%. Figure 8 The results showed that the material had good reusability and could effectively remove dyes from aqueous solutions.

[0075] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other 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.

[0076] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for preparing a phosphorus-oxygen functionalized hyper-crosslinked porous polymer material, characterized in that: The following steps are involved: Take tetraphenylmethane as raw material, add liquid bromine, and a substitution reaction occurs to obtain tetraphenylmethane bromide; Using diethyl phosphite and tetraphenyltoluene 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 subjected to hydrolysis treatment in an acid solution to obtain a crude product of the phosphate-modified tetraphenylmethane; Under a protective atmosphere, 1,2-dichloroethane is used as a solvent, a crude product of phosphate-modified tetraphenylmethane is used as a raw material, and dimethoxymethane is used as a cross-linking agent. Under the action of a second catalyst, an alkylation reaction occurs 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 with 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 tetraphenyltoluene 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 under magnetic stirring at 85°C-90°C for 5h-6h.

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 3g~5g:20mL, and the hydrolysis reaction is carried out at room temperature for 12h~14h.

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 anhydrous ferric chloride 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-crosslinked porous polymer material is 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.

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