Porous organic polymers based on benzyl alcohol structure, and preparation method and application thereof

Abstract

The application discloses a porous organic polymer based on benzyl alcohol structure and a preparation method and application thereof, relates to the field of organic photocatalytic materials, and comprises the following steps: dissolving monomer I and monomer II in solvent I; after dissolving, a catalyst is added and reaction is carried out under an inert gas atmosphere; after the reaction is completed, the filter cake is filtered and washed with solvent II; the obtained solid powder is eluted in a Soxhlet extractor, and the porous organic polymer based on benzyl alcohol structure is obtained after vacuum drying; the porous organic polymer containing benzyl alcohol structure is synthesized by one step of the Friedel-Crafts reaction of benzyl alcohol and derivatives thereof and chloromethyl aromatic hydrocarbon; the synthesis method is simple, and the yield is relatively high; the prepared porous organic polymer has good photocatalytic performance, and can efficiently produce hydrogen peroxide under photocatalytic conditions; and the application provides a new method and new idea which are simple to operate, effective and feasible for the design and research and development of photocatalysts.

Description

Technical Field

[0001] The present invention relates to the field of organic photocatalytic materials, and in particular to a porous organic polymer based on a benzyl alcohol structure, a preparation method and an application thereof. Background Art

[0002] Hydrogen peroxide is an important chemical reagent, often used as a green oxidant, disinfectant, bleaching agent, and energy carrier. However, the current mainstream method for industrial production of hydrogen peroxide is the anthraquinone process. This energy-intensive method has many disadvantages, including high production costs and significant risks in production safety and environmental protection. Therefore, it is imperative to develop low-cost, low-energy, and environmentally friendly hydrogen peroxide production processes. Currently, the sustainable production of hydrogen peroxide using photosynthesis is an effective alternative.

[0003] To date, various semiconductor materials have been used for photocatalytic hydrogen peroxide production, such as g-C3N4, metal-organic frameworks (MOFs), and porous organic polymers (POPs). POPs have garnered widespread attention in the field of photocatalysis due to their high surface area, low density, good stability, and uniform pore size.

[0004] However, the concentration of hydrogen peroxide produced by photocatalytic production using POPs is still at the μM level, which is insufficient for industrial production. Therefore, the development of an efficient photocatalyst is urgent. Research has found that a two-phase system of benzyl alcohol and water can efficiently produce hydrogen peroxide under photocatalytic conditions. However, this two-phase system produces byproducts such as benzaldehyde and benzoic acid under light, which is not conducive to their recovery. POPs have the advantages of strong stability and easy recycling. Combining the high efficiency of benzyl alcohol in producing hydrogen peroxide with the strong stability and easy recycling characteristics of POPs is the main challenge currently faced. Summary of the Invention

[0005] To provide a low-cost, low-energy, and environmentally friendly hydrogen peroxide production process that does not produce byproducts such as benzaldehyde and benzoic acid, and solves the problem of small molecule benzyl alcohol producing byproduct benzoic acid under photocatalytic conditions, which affects the purity of hydrogen peroxide, the present invention provides the following technical solutions:

[0006] Porous organic polymer based on benzyl alcohol structure, the structural formula is as follows:

[0007]

[0008] Among them, n=1, 2.

[0009] The synthetic reaction formula of porous organic polymer based on benzyl alcohol structure is as follows:

[0010]

[0011] Wherein, in the structure shown in monomer I: R1, R2, and R3 are independently selected from H or CH2OH; in the structure shown in monomer II, n=1, 2; and X is a halogen.

[0012] The present invention also discloses a method for preparing a porous organic polymer based on a benzyl alcohol structure, comprising the following steps:

[0013] S1, dissolving monomer I and monomer II in a solvent;

[0014] S2. Under an inert gas atmosphere, adding a catalyst and heating to react to obtain a first product;

[0015] S3, filtering the first product to obtain a filter cake;

[0016] S4. Washing the filter cake and eluting it in a Soxhlet extractor, and drying it to obtain a porous organic polymer based on a benzyl alcohol structure.

[0017] Preferably, the molar ratio of monomer I to monomer II in S1 is: 0.2-2 g, 2-10 mmol: 0.2-2.5 g, 2-10 mmol.

[0018] Preferably, in S1, the solvent is at least one of chloroform, N,N-dimethylformamide, diisopropylamine, tetrahydrofuran, methanol, ethanol, 1,4-dioxane, acetonitrile, and toluene.

[0019] Preferably, in S2, the catalyst is at least one of aluminum trichloride, ferric chloride, and boron trifluoride etherate, and the amount of the catalyst is: 3-6 g, 30-50 mmol; the inert gas is argon or nitrogen, and the temperature reaction method is to raise the temperature to 50-100°C and react for not less than 72 hours.

[0020] Preferably, in S4, the filter cake is washed using at least one of dichloromethane, methanol, tetrahydrofuran, water, dilute hydrochloric acid, acetone, ether, and N,N-dimethylformamide.

[0021] Preferably, in S4, the elution method is: eluting with at least one of dichloromethane, methanol, tetrahydrofuran, water, dilute hydrochloric acid, acetone, ether, and N,N-dimethylformamide in a Soxhlet extractor for 12 to 48 hours, and the drying method is: vacuum drying at 40 to 60° C. for not less than 24 hours.

[0022] The present invention also applies the porous organic polymer based on the benzyl alcohol structure to photocatalytic production of hydrogen peroxide.

[0023] The present invention also discloses the application of a porous organic polymer based on a benzyl alcohol structure, comprising the following steps:

[0024] Weigh 2.5-10 mg of a porous organic polymer based on a benzyl alcohol structure and 20 mL of a feed solution into a centrifuge tube and ultrasonically disperse for 5-10 minutes. Then, transfer the mixture to a constant temperature reactor and circulate water to keep the mixture in a state of continuous stirring at 25°C. Use a 300-watt xenon lamp to continuously illuminate the reactor. Take 2 mL of the reaction solution every 60 minutes and filter it using a 0.22 μm filter.

[0025] The present invention has the following beneficial effects: the present invention synthesizes a porous organic polymer containing a benzyl alcohol structure by a Friedel-Crafts reaction of benzyl alcohol and its derivatives with chloromethyl aromatic hydrocarbons in one step. The synthesis method is simple and has a high yield. The prepared porous organic polymer has good photocatalytic properties and can efficiently produce hydrogen peroxide under photocatalytic conditions.

[0026] The exposed benzyl alcohol functional group in this invention not only retains its hydrogen peroxide-producing properties but also addresses the issue of benzoic acid, a byproduct produced by small-molecule benzyl alcohol under photocatalytic conditions, which can affect the purity of hydrogen peroxide. This invention provides a simple, effective, and feasible new method and approach for the design and development of photocatalysts, which is of great significance for improving hydrogen peroxide production from photocatalytic POPs. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The water contact angle of the porous organic polymer PBA2B-31 based on the benzyl alcohol structure prepared in Example 10;

[0028] Figure 2a This is the infrared spectrum of the porous organic polymer based on the benzyl alcohol structure prepared in Example 1-4;

[0029] Figure 2b This is the infrared spectrum of the porous organic polymer based on benzyl alcohol structure prepared in Examples 5-8;

[0030] Figure 2c IR spectra of the porous organic polymers based on benzyl alcohol structure prepared in Examples 9-13;

[0031] Figure 3 This is an X-ray diffraction pattern of the porous organic polymer PBA2B-31 based on the benzyl alcohol structure prepared in Example 10;

[0032] Figure 4 X-ray photoelectron spectrum of the porous organic polymer PBA2B-31 based on benzyl alcohol structure prepared in Example 10;

[0033] Figure 5 The electrochemical impedance spectroscopy of the porous organic polymer PBA2B-31 based on the benzyl alcohol structure prepared in Example 10;

[0034] Figure 6This is a photocurrent diagram of the porous organic polymer PBA2B-31 based on the benzyl alcohol structure prepared in Example 10;

[0035] Figure 7 This is a graph showing the photocatalytic hydrogen peroxide production rate of the porous organic polymer PBA2B-31 based on the benzyl alcohol structure prepared in Example 10 at different catalyst concentrations;

[0036] Figure 8 This is a graph showing the photocatalytic hydrogen peroxide production rate of the porous organic polymer PBA2B-31 based on the benzyl alcohol structure prepared in Example 10 under different atmospheres. DETAILED DESCRIPTION

[0037] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below in conjunction with specific implementation methods.

[0038] Example 1: A porous organic polymer BAB based on a benzyl alcohol structure, the structural formula of which is as follows:

[0039]

[0040] The synthesis method of the above polymer is as follows:

[0041]

[0042] (1) Benzyl alcohol (1.78 g, 16 mmol), p-dichlorobenzyl (1.4 g, 8 mmol), and 50 mL of chloroform were added to a three-necked flask equipped with a magnetic rod and stirred under a nitrogen atmosphere for 15-30 minutes;

[0043] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (5.3 g, 40 mmol) is added to the above solution in small amounts and in multiple batches. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours.

[0044] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0045] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50° C. for 24 hours to obtain a porous organic polymer BAB based on a benzyl alcohol structure with a yield of 83%.

[0046] Example 2: A porous organic polymer PBAB based on a benzyl alcohol structure, the structural formula of which is as follows:

[0047]

[0048] The synthesis method of the above polymer is as follows:

[0049]

[0050] (1) Add p-benzhydrol (1.38 g, 10 mmol), p-dichlorobenzyl (900 mg, 5 mmol), and 50 mL of chloroform to a three-necked flask equipped with a magnetic rod and stir under a nitrogen atmosphere for 15-30 minutes;

[0051] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (4 g, 30 mmol) is added to the above solution in small amounts and several times. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours;

[0052] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0053] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50° C. for 24 hours to obtain a porous organic polymer PBAB based on a benzyl alcohol structure with a yield of 84%.

[0054] Example 3: A porous organic polymer OBAB based on a benzyl alcohol structure, the structural formula of which is as follows:

[0055]

[0056] The synthesis method of the above polymer is as follows:

[0057]

[0058] (1) Add o-benzyl alcohol (1.38 g, 10 mmol), p-dichlorobenzyl (900 mg, 5 mmol), and 50 mL of chloroform to a three-necked flask equipped with a magnetic rod and stir under a nitrogen atmosphere for 15-30 minutes;

[0059] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (4 g, 30 mmol) is added to the above solution in small amounts and several times. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours;

[0060] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0061] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50° C. for 24 hours to obtain a porous organic polymer based on a benzyl alcohol structure, OBAB, with a yield of 83%.

[0062] Example 4: A porous organic polymer MBAB based on a benzyl alcohol structure, having the following structural formula:

[0063]

[0064] The synthesis method of the above polymer is as follows:

[0065]

[0066] (1) Add s-tribenzyl alcohol (168 mg, 1 mmol), p-dichlorobenzyl (88 mg, 0.5 mmol), and 10 mL of chloroform to a three-necked flask equipped with a magnetic rod and stir under a nitrogen atmosphere for 15-30 minutes;

[0067] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (400 mg, 3 mmol) is added to the above solution in small amounts and several times. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours.

[0068] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0069] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50° C. for 24 hours to obtain a porous organic polymer MBAB based on a benzyl alcohol structure with a yield of 86%.

[0070] Example 5: A porous organic polymer BA2B based on a benzyl alcohol structure, having the following structural formula:

[0071]

[0072] The synthesis method of the above polymer is as follows:

[0073]

[0074] (1) Benzyl alcohol (1.73 g, 16 mmol), biphenyl dichlorobenzyl (2.01 g, 8 mmol), and 50 mL of chloroform were added to a three-necked flask equipped with a magnetic rod and stirred under a nitrogen atmosphere for 15-30 minutes;

[0075] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (5.3 g, 40 mmol) is added to the above solution in small amounts and in multiple batches. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours.

[0076] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0077] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50°C for 24 hours to obtain a porous organic polymer BA2B based on a benzyl alcohol structure with a yield of 84%.

[0078] Example 6: A porous organic polymer PBA2B based on a benzyl alcohol structure, having the following structural formula:

[0079]

[0080] The synthesis method of the above polymer is as follows:

[0081]

[0082] (1) Add benzhydrol (1.38 g, 10 mmol), diphenylbenzyl chloride (1.3 g, 10 mmol), and 50 mL of chloroform to a three-necked flask equipped with a magnetic rod and stir under a nitrogen atmosphere for 15-30 minutes;

[0083] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (4 g, 30 mmol) is added to the above solution in small amounts and several times. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours;

[0084] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0085] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50° C. for 24 hours to obtain a porous organic polymer PBA2B based on a benzyl alcohol structure with a yield of 82%.

[0086] Example 7: A porous organic polymer OBA2B based on a benzyl alcohol structure, having the following structural formula:

[0087]

[0088] The synthesis method of the above polymer is as follows:

[0089]

[0090] (1) Add o-benzyl alcohol (1.38 g, 10 mmol), biphenyl dichloride (1.3 g, 5 mmol), and 50 mL of chloroform to a three-necked flask equipped with a magnetic rod and stir under a nitrogen atmosphere for 15-30 minutes;

[0091] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (4 g, 30 mmol) is added to the above solution in small amounts and several times. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours;

[0092] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0093] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50° C. for 24 hours to obtain a porous organic polymer OBA2B based on a benzyl alcohol structure with a yield of 83%.

[0094] Example 8: A porous organic polymer MBA2B based on a benzyl alcohol structure, having the following structural formula:

[0095]

[0096] The synthesis method of the above polymer is as follows:

[0097]

[0098] (1) Add s-tribenzyl alcohol (168 mg, 1 mmol), biphenyl dichlorobenzyl (125 mg, 0.5 mmol), and 10 mL of chloroform to a three-necked flask equipped with a magnetic rod and stir under a nitrogen atmosphere for 15-30 minutes;

[0099] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (400 mg, 3 mmol) is added to the above solution in small amounts and several times. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours.

[0100] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0101] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50° C. for 24 hours to obtain a porous organic polymer MBA2B based on a benzyl alcohol structure with a yield of 86%.

[0102] Example 9: A porous organic polymer PBA2B-51 based on a benzyl alcohol structure, having the following structural formula:

[0103]

[0104] The synthesis method of the above polymer is as follows:

[0105]

[0106] (1) Add benzhydrol (1.65 g, 12 mmol), biphenyl dichlorobenzyl (600 mg, 2.4 mmol), and 50 mL of chloroform to a three-necked flask equipped with a magnetic rod and stir under a nitrogen atmosphere for 15-30 minutes;

[0107] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (4 g, 30 mmol) is added to the above solution in small amounts and several times. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours;

[0108] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0109] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50° C. for 24 hours to obtain a porous organic polymer PBA2B-51 based on a benzyl alcohol structure with a yield of 88%.

[0110] Example 10: A porous organic polymer PBA2B-31 based on a benzyl alcohol structure, having the following structural formula:

[0111]

[0112] The synthesis method of the above polymer is as follows:

[0113]

[0114] (1) Add benzhydrol (1.24 g, 9 mmol), diphenylbenzyl chloride (750 mg, 3 mmol), and 50 mL of chloroform to a three-necked flask equipped with a magnetic rod and stir under a nitrogen atmosphere for 15-30 minutes;

[0115] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (4 g, 30 mmol) is added to the above solution in small amounts and several times. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours;

[0116] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0117] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50° C. for 24 hours to obtain a porous organic polymer PBA2B-31 based on a benzyl alcohol structure with a yield of 84%.

[0118] Example 11: A porous organic polymer PBA2B-11 based on a benzyl alcohol structure, having the following structural formula:

[0119]

[0120] The synthesis method of the above polymer is as follows:

[0121]

[0122] (1) Add benzhydrol (828 mg, 6 mmol), biphenyl dichlorobenzyl (1.5 g, 6 mmol), and 50 mL of chloroform to a three-necked flask equipped with a magnetic rod and stir under a nitrogen atmosphere for 15-30 minutes;

[0123] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (4 g, 30 mmol) is added to the above solution in small amounts and several times. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours;

[0124] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0125] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50° C. for 24 hours to obtain a porous organic polymer PBA2B-11 based on a benzyl alcohol structure with a yield of 85%.

[0126] Example 12: A porous organic polymer PBA2B-13 based on a benzyl alcohol structure, having the following structural formula:

[0127]

[0128] The synthesis method of the above polymer is as follows:

[0129]

[0130] (1) Add benzhydrol (414 mg, 3 mmol), diphenylbenzyl chloride (2.3 g, 9 mmol), and 50 mL of chloroform to a three-necked flask equipped with a magnetic rod and stir under a nitrogen atmosphere for 15-30 minutes;

[0131] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (4 g, 30 mmol) is added to the above solution in small amounts and several times. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours;

[0132] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0133] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50° C. for 24 hours to obtain a porous organic polymer PBA2B-13 based on a benzyl alcohol structure with a yield of 82%.

[0134] Example 13: A porous organic polymer PBA2B-15 based on a benzyl alcohol structure, having the following structural formula:

[0135]

[0136] The synthesis method of the above polymer is as follows:

[0137]

[0138] (1) Add benzhydrol (276 mg, 2 mmol), diphenylbenzyl chloride (2.5 g, 10 mmol), and 50 mL of chloroform to a three-necked flask equipped with a magnetic rod and stir under a nitrogen atmosphere for 15-30 minutes;

[0139] (2) After the solid in step (1) is completely dissolved, anhydrous aluminum chloride (4 g, 30 mmol) is added to the above solution in small amounts and several times. After dispersion under a nitrogen atmosphere, the mixed solution is heated to 70° C. and refluxed for 72 hours;

[0140] (3) After the reaction is completed, the reaction system is cooled to room temperature and poured into ice water. The filter cake is obtained by suction filtration and washed with water, dilute hydrochloric acid, methanol, and dichloromethane in sequence;

[0141] (4) The filter cake obtained in step (3) was transferred to a Soxhlet extractor and eluted with tetrahydrofuran, methanol, and dichloromethane in sequence for 48 hours. The eluted filter cake was placed in a vacuum oven and vacuum-dried at 50°C for 24 hours to obtain a porous organic polymer PBA2B-15 based on a benzyl alcohol structure with a yield of 83%. Study on the photocatalytic production of hydrogen peroxide by different porous organic polymers:

[0142] The porous organic polymer based on the benzyl alcohol structure obtained in Examples 1-8 was used to study the photocatalytic production of hydrogen peroxide;

[0143] Test method: 5 mg of the benzyl alcohol-structured porous organic polymer prepared in Examples 1-8 above was weighed and added to 20 mL of pure water, then ultrasonically dispersed in a centrifuge tube for 5-10 minutes. The mixture was then transferred to a thermostatic reactor, stirred continuously at 25°C through a circulating water system, and illuminated continuously with a 300-watt xenon lamp. After 60 minutes, 2 mL of the reaction solution was collected and filtered using a 0.22 μm filter. 1.5 mL of the resulting filtrate was transferred to a centrifuge tube, and 1 mL of 1 mol L -1 The potassium titanium oxalate aqueous solution was mixed and reacted for 5 minutes, and then the absorbance was measured by UV-visible spectrophotometer. The concentration of hydrogen peroxide was determined according to the standard curve, as shown in Table 1.

[0144] Table 1

[0145]

[0146]

[0147] Study on photocatalytic production of hydrogen peroxide at different catalyst concentrations:

[0148] The porous organic polymer based on the benzyl alcohol structure obtained in Example 10 was used to study the photocatalytic production of hydrogen peroxide at different catalyst concentrations.

[0149] Test Method: 2.5 mg, 5 mg, and 10 mg of the benzyl alcohol-structured porous organic polymer prepared in Example 10 above were weighed and added to 20 mL of pure water into a centrifuge tube for ultrasonic dispersion for 5-10 minutes. The mixture was then transferred to a thermostatic reactor and continuously stirred at 25°C under circulating water. The reactor was continuously illuminated with a 300-watt xenon lamp. After 60 minutes, 2 mL of the reaction solution was removed and filtered using a 0.22 μm filter. 1.5 mL of the resulting filtrate was transferred to a centrifuge tube, and 1 mL of a 1 mol / L potassium titanium oxalate aqueous solution was added. After mixing for 5 minutes, the absorbance was measured using a UV-visible spectrophotometer. The hydrogen peroxide concentration was determined using a standard curve, as shown in Table 2.

[0150] Table 2

[0151] <![CDATA[Catalyst concentration (mg mL -1 )]]> <![CDATA[Hydrogen peroxide production (mmol g -1 h -1 )]]> 1.25 3.72 2.5 3.94 5 2.93

[0152] Study on photocatalytic production of hydrogen peroxide under different water sources:

[0153] The porous organic polymer based on the benzyl alcohol structure obtained in Example 10 was used to study the photocatalytic production of hydrogen peroxide under different water sources.

[0154] Test Method: 5 mg of the benzyl alcohol-structured porous organic polymer prepared in Example 10 was weighed and mixed with 20 mL of pure water, river water, tap water, seawater, and Yangtze River water, respectively, in a centrifuge tube and ultrasonically dispersed for 5-10 minutes. The mixture was then transferred to a thermostatic reactor, where circulating water was maintained at 25°C under constant stirring. The reactor was continuously illuminated with a 300-watt xenon lamp. After 60 minutes, 2 mL of the reaction solution was removed and filtered through a 0.22 μm filter. 1.5 mL of the resulting filtrate was transferred to a centrifuge tube, and 1 mL of a 1 mol / L potassium titanium oxalate aqueous solution was added. After mixing for 5 minutes, the absorbance was measured using a UV-visible spectrophotometer. The hydrogen peroxide concentration was determined using a standard curve, as shown in Table 3.

[0155] Table 3

[0156] water source <![CDATA[Hydrogen peroxide production (mmol g -1 h -1 )]]> pure water 3.94 Yangtze River Water 4.50 river water 4.70 seawater 4.01 Tap water 3.91

[0157] Study on photocatalytic production of hydrogen peroxide at different pH:

[0158] The porous organic polymer based on the benzyl alcohol structure obtained in Example 10 was used to study the photocatalytic production of hydrogen peroxide under different pH conditions.

[0159] Experimental Method: 5 mg of the benzyl alcohol-structured porous organic polymer prepared in Example 10 was weighed and mixed with 20 mL of solutions at pH 3, pH 5, pH 7, pH 9, and pH 11, respectively, into centrifuge tubes and ultrasonically dispersed for 5-10 minutes. The mixture was then transferred to a thermostatic reactor, stirred continuously at 25°C through a circulating water system, and illuminated continuously with a 300-watt xenon lamp. After 60 minutes, 2 mL of the reaction solution was removed and filtered through a 0.22 μm filter. 1.5 mL of the resulting filtrate was transferred to a centrifuge tube, and 1 mL of a 1 mol / L potassium titanium oxalate aqueous solution was added. After mixing for 5 minutes, the absorbance was measured using a UV-visible spectrophotometer. The hydrogen peroxide concentration was determined using a standard curve, as shown in Table 4.

[0160] Table 4

[0161] pH <![CDATA[Hydrogen peroxide production (mmol g -1 h -1 )]]> 3 4.01 5 3.77 7 3.94 9 4.50 11 4.14

[0162] Study on long-term cumulative photocatalytic production of hydrogen peroxide:

[0163] The porous organic polymer based on the benzyl alcohol structure obtained in Example 10 was subjected to a long-term cumulative photocatalytic oxidation in an air atmosphere to study the production of hydrogen peroxide;

[0164] Experimental Method: 5 mg of the benzyl alcohol-structured porous organic polymer prepared in Example 10 was weighed and added to 20 mL of pure water in a centrifuge tube for ultrasonic dispersion for 5-10 minutes. The mixture was then transferred to a thermostatic reactor, where it was continuously stirred at 25°C and illuminated with a 300-W xenon lamp. Every 60 minutes, 2 mL of the reaction solution was filtered through a 0.22 μm filter. 1.5 mL of the resulting filtrate was transferred to a centrifuge tube, and 1 mL of a 1 mol / L aqueous solution of potassium titanium oxalate was added. After mixing for 5 minutes, the absorbance was measured using a UV-visible spectrophotometer. The hydrogen peroxide concentration was determined using a standard curve, as shown in Table 5.

[0165] Table 5

[0166] Photoperiod (h) <![CDATA[Hydrogen peroxide production (mmol g -1 h -1 )]]> 0 0 1 3.72 2 6.36 3 7.60 4 8.85 5 10.19 6 11.55 7 12.58

[0167] It is understood from common technical knowledge that the present invention may be implemented by other embodiments that do not depart from its spirit or essential features. Therefore, the embodiments disclosed above are, in all respects, merely illustrative and not exclusive. All modifications within the scope of the present invention or equivalent to the scope of the present invention are intended to be encompassed by the present invention.

Claims

1. Application of porous organic polymers based on benzyl alcohol structure in photocatalytic production of hydrogen peroxide, characterized in that: The structural formula of porous organic polymer is as follows: Wherein, n = 1, 2; R1, R2, R3 are independently selected from H or CH2OH.

2. The use of the porous organic polymer based on benzyl alcohol structure in photocatalytic production of hydrogen peroxide according to claim 1, characterized in that: The synthetic reaction formula is as follows: Among them, in the structure shown in monomer II, n = 1, 2; X is a halogen.

3. The use of the porous organic polymer based on benzyl alcohol structure in photocatalytic production of hydrogen peroxide according to claim 2, characterized in that: The preparation method of the porous organic polymer comprises the following steps: S1, dissolving monomer I and monomer II in a solvent; S2. Under an inert gas atmosphere, adding a catalyst and heating to react to obtain a first product; S3, filtering the first product to obtain a filter cake; S4. Washing the filter cake and eluting it in a Soxhlet extractor, and drying it to obtain a porous organic polymer based on a benzyl alcohol structure.

4. The use of the porous organic polymer based on benzyl alcohol structure in photocatalytic production of hydrogen peroxide according to claim 3, characterized in that: The molar ratio of monomer I to monomer II in S1 is: 2-10 mmol:2-10 mmol.

5. The use of the porous organic polymer based on benzyl alcohol structure in photocatalytic production of hydrogen peroxide according to claim 3, characterized in that: In S1, the solvent is chloroform, N , N- At least one of dimethylformamide, diisopropylamine, tetrahydrofuran, methanol, ethanol, 1,4-dioxane, acetonitrile, and toluene.

6. The use of the porous organic polymer based on benzyl alcohol structure in photocatalytic production of hydrogen peroxide according to claim 3, characterized in that: In S2, the catalyst is at least one of aluminum trichloride, ferric chloride, and boron trifluoride etherate, and the amount of the catalyst is 30-50 mmol; the inert gas is argon or nitrogen, and the temperature reaction method is to raise the temperature to 50-100°C and react for not less than 72 hours.

7. The use of the porous organic polymer based on benzyl alcohol structure in photocatalytic production of hydrogen peroxide according to claim 3, characterized in that: In S4, the filter cake is washed with dichloromethane, methanol, tetrahydrofuran, water, dilute hydrochloric acid, acetone, ether, N , N -dimethylformamide to wash the filter cake.

8. The use of the porous organic polymer based on benzyl alcohol structure in photocatalytic production of hydrogen peroxide according to claim 3, characterized in that: In S4, the elution method is: using dichloromethane, methanol, tetrahydrofuran, water, dilute hydrochloric acid, acetone, ether, N , N -dimethylformamide for 12 to 48 hours, and the drying method is: vacuum drying at 40 to 60 ° C for not less than 24 hours.

9. The use of the porous organic polymer based on benzyl alcohol structure in photocatalytic production of hydrogen peroxide according to claim 1, characterized in that: The steps include: Weigh 2.5-10 mg of a porous organic polymer based on a benzyl alcohol structure and 20 mL of the feed solution into a centrifuge tube and ultrasonically disperse for 5-10 minutes. Then transfer the mixture to a constant temperature reactor and circulate water to keep the mixture in a state of continuous stirring at 25°C. Use a 300-watt xenon lamp to continuously illuminate the reactor. Take 2 mL of the reaction solution every 60 minutes and filter it using a 0.22 μm filter.

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