Composite particle material for water ecological restoration and preparation method and application thereof

Abstract

The application discloses a water ecological restoration composite particle material in the technical field of water purification, a preparation method and application thereof, and comprises the following components in parts by weight: 60-70 parts of an anti-seepage agent, 5-8 parts of montmorillonite, 5-10 parts of nano-hydroxyapatite, 5-8 parts of nano-silicon dioxide and 3-5 parts of polyvinyl alcohol. The composite material formed by the cyclodextrin inclusion compound and the benzene-containing polysiloxane-PCL improves the adsorption of the composite particle to harmful substances in the water environment, the hydrophilic and hydrophobic cooperation between the polyvinyl alcohol and the benzene-containing polysiloxane-PCL forms the anti-seepage barrier with low permeability and high expansion, the composite particle material has high water purification function, meanwhile, the anti-seepage performance blocks the migration path of pollutants, and a closed loop system of restoration and blocking is formed.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of water quality purification, and particularly relates to a composite particle material for water ecological restoration and a preparation method and application thereof. BACKGROUND

[0002] With the acceleration of urbanization and industrialization, water pollution has become a major environmental problem worldwide. Black and odorous water, eutrophication, heavy metal pollution, and other problems not only destroy aquatic ecosystems, but also threaten human health. Traditional water ecological restoration technologies (such as source control, chemical flocculation, and biological membrane method) have limitations: source control is the core of water ecological restoration, which cuts off the path of pollutants (such as domestic sewage, industrial wastewater, and initial rainwater) into water bodies (such as building separate rainwater and sewage pipe networks, plugging sewage outlets, and treating industrial pollution sources), and fundamentally reduces pollutant input. However, its technical characteristics determine that there are three core problems in the implementation process: long cycle, high cost, and difficulty in old city reconstruction, making it difficult to quickly improve water quality; chemical treatment quickly removes pollutants in water by adding chemical agents (such as flocculants, oxidants, and disinfectants), such as using polyaluminum chloride (PAC) to flocculate suspended solids and using sodium hypochlorite to disinfect and sterilize. The short-term purification effect is significant, but the residues of the agents or reaction byproducts may bring new environmental risks. Excessive use of inorganic flocculants (such as aluminum and iron salts) and organic flocculants (such as polyacrylamide) may cause multiple problems, including the generation of toxic byproducts. To control water odor or pathogenic bacteria, disinfectants such as chlorine, ozone, and chlorine dioxide are often used, but disinfectants can react with natural organic matter (such as humic acid) in water to generate toxic byproducts. Biological restoration relies on the metabolic activity of microorganisms (such as aerobic bacteria, anaerobic bacteria, and photosynthetic bacteria), aquatic plants (such as reeds and canes), or biological membranes to degrade organic matter and transform nitrogen and phosphorus in water. This method has the advantages of environmental protection and low cost, but the activity of microorganisms is easily affected by environmental conditions such as temperature, pH, and dissolved oxygen, leading to large fluctuations in restoration effects. Sediment is a reservoir of pollutants, accumulating large amounts of nitrogen, phosphorus, heavy metals, and difficult-to-degrade organic matter (such as polycyclic aromatic hydrocarbons). Traditional sediment treatment mainly uses mechanical dredging (such as cutter suction dredgers and grab dredgers) to remove contaminated sediment from water bodies, but this process easily disturbs the sediment and releases pollutants, and the disposal of dredged sediment becomes a new environmental burden. Microbial composite materials can in situ repair sediment, activate indigenous microorganisms, increase dissolved oxygen concentration, and adsorb ammonia and phosphate using mineral hydrogels (such as calcium phosphate and struvite) to inhibit algal growth while recycling nutrients into fertilizers. Iron oxide and diatomite can chelate and solidify lead and chromium to reduce their bioavailability. TiO2-montmorillonite composite materials can destroy algal cell membranes under ultraviolet light, with an algae removal rate of 94.58%. Nano-Cu / C composite materials can inhibit Microcystis aeruginosa through oxidative stress, with a longer algae control period than traditional CuSO4. Composite particles containing nanoparticles (such as In2O3 and Cu / C) can be enriched by aquatic organisms (such as plankton and fish).Nanoparticles will accumulate through the food chain, causing potential harm to higher trophic level organisms (such as birds), and the carriers of some composite particles (such as polyphenylene sulfide, polyacetal) cannot be naturally degraded, even if recycled magnetically, there are still 10%-15% of small fragments remaining in the sediment, long-term accumulation will change the sediment structure, affect the habitat environment of benthic organisms (such as snails, mussels). SUMMARY

[0003] In view of the above, in order to overcome the defects of the prior art, the application provides a composite particle material for water ecological restoration and a preparation method and application thereof. The composite material formed by cyclodextrin inclusion compound and phenylene polysiloxane-PCL improves the adsorption of harmful substances in the water environment. The hydrophilic and hydrophobic combination between polyvinyl alcohol and phenylene polysiloxane-PCL forms a low-permeability and high-swelling anti-seepage barrier, so that the composite particle material has high water purification function, and the anti-seepage performance blocks the migration path of pollutants, forming a closed-loop system of restoration and blocking.

[0004] To achieve the above purpose, the technical scheme adopted by the application is as follows: the application provides a composite particle material for water ecological restoration, which comprises the following components in parts by weight: anti-seepage agent 60-70 parts, montmorillonite 5-8 parts, nano-hydroxyapatite 5-10 parts, nano-silicon dioxide 5-8 parts, polyvinyl alcohol 3-5 parts;

[0005] Preferably, the preparation raw material of the anti-seepage agent is composed of the following components in parts by weight: phenylene polysiloxane-PCL 5-7.2 parts, cyclodextrin inclusion compound 1-1.5 parts;

[0006] Preferably, the preparation method of the phenylene polysiloxane-PCL specifically comprises the following steps:

[0007] A1, dissolve 2,5-dibromophenol in anhydrous DMF, pass flowing nitrogen, add imidazole and stir until dissolution, slowly add t-butyldimethylsilyl chloride / DMF solution to the reaction system, and carry out protection reaction at room temperature. After the reaction is completed, saturated NaCl aqueous solution is added for washing, and ethyl acetate is added for repeated extraction. The water in the organic phase is dried with anhydrous sodium sulfate, the excess reaction solvent is removed by rotary evaporation, and 2,5-dibromophenol-TBDMS is obtained;

[0008] Preferably, in step A1, the mass ratio between the 2,5-dibromophenol and imidazole is 2.5:1.4-1.8;

[0009] Preferably, in step A1, the mass ratio between the 2,5-dibromophenol and t-butyldimethylsilyl chloride is 2.5:1.8-2.2;

[0010] A2, take magnesium and iodine particles in the flask, under nitrogen atmosphere, add anhydrous THF, stirring until the iodine fade, the 2, 5-dibromophenol-TBDMS prepared in step A1 is dissolved in anhydrous THF, slowly added to the reaction system, after the dropwise addition is completed, the Grignard reaction is carried out by increasing the reaction temperature, after the reaction is completed, 2, 5-bis (magnesium bromide) phenoxy-TBDMS reaction solution is obtained;

[0011] Preferably, in step A2, the mass ratio between the magnesium and iodine particles is 4-6:1;

[0012] Preferably, in step A2, the mass ratio between the magnesium and the 2, 5-dibromophenol in step A1 is 0.4-0.6:2.5;

[0013] Preferably, in step A2, the reaction temperature of Grignard reaction is 40-50℃, and the reaction time of Grignard reaction is 1-2h;

[0014] A3, take the 2, 5-bis (magnesium bromide) phenoxy-TBDMS reaction solution prepared in step A2 and place it in an ice water bath for cooling. After cooling to 0℃, slowly add dimethyldiethoxysilane / THF solution under nitrogen atmosphere. After the dropwise addition is completed, keep the ice water bath condition for pre-reaction. After 1-2h, increase the reaction temperature to room temperature for silanization reaction. After 3-5h, add 0℃ saturated NH4Cl aqueous solution for quenching reaction. Add ethyl acetate for repeated extraction. Combine the organic phase, dry the water in the organic phase with anhydrous sodium sulfate, remove the excess reaction solvent by rotary evaporation, and obtain phenylene siloxane monomer-TBDMS;

[0015] Preferably, in step A3, the mass ratio between the dimethyldiethoxysilane and the 2, 5-dibromophenol in step A1 is 1.8-2.4:2.5;

[0016] A4, take the phenylene siloxane monomer-TBDMS prepared in step A3 and dissolve it in anhydrous toluene. Add ε-caprolactone and stannous octoate. After vacuum degassing for 3 times, fill nitrogen. Increase the reaction temperature for polymerization reaction. After the reaction is completed, cool down. Add THF to dissolve the reaction product. Add 4℃ anhydrous methanol for alcohol precipitation. Filter, collect the precipitate, and vacuum dry to obtain phenylene polysiloxane-PCL-TBDMS;

[0017] Preferably, in step A4, the mass ratio between the phenylene siloxane monomer-TBDMS and ε-caprolactone is 2.0-3.0:4.2-6.5;

[0018] Preferably, in step A4, the added mass of stannous octoate is 0.2%-0.3% of the mass of ε-caprolactone;

[0019] Preferably, in step A4, the reaction temperature of the polymerization reaction is 120-130°C, the reaction time of the polymerization reaction is 14-18h, and the stirring speed of the polymerization reaction is 300-400rpm;

[0020] A5, the phenylene polysiloxane-PCL-TBDMS prepared in step A4 is dissolved in anhydrous THF, tetrabutylammonium fluoride solution is added, and stirring is performed at room temperature at a speed of 300-500rpm for 2-3h, then the reaction system is poured into deionized water at 4°C, dichloromethane is added for extraction, the organic phase is collected, anhydrous sodium sulfate is used to remove water from the organic phase, the solvent is evaporated, anhydrous methanol is added for alcohol precipitation, the precipitate is collected, and vacuum drying is performed to obtain phenylene polysiloxane-PCL;

[0021] Preferably, the preparation method of the impermeable agent specifically comprises the following steps:

[0022] S1, β-cyclodextrin is placed in deionized water, heated and stirred until completely dissolved, aliphatic diacid is added, and the reaction temperature is maintained for inclusion reaction, after the reaction is completed, cooling is performed, 4°C static treatment is performed, filtration is performed, the filter cake is collected, repeatedly washed with 4°C anhydrous ethanol, and vacuum drying is performed to obtain a cyclodextrin inclusion compound;

[0023] Preferably, in step S1, the aliphatic diacid comprises at least one of adipic acid, pimelic acid, suberic acid, and azelaic acid;

[0024] Preferably, in step S1, the mass ratio between the β-cyclodextrin and the aliphatic diacid is 6.8:0.85-1.0;

[0025] Preferably, in step S1, the reaction temperature of the inclusion reaction is 70-80°C, and the reaction time of the inclusion reaction is 1-2h;

[0026] S2, the cyclodextrin inclusion compound prepared in step S1 is dissolved in DMF, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide are dissolved in MES buffer to obtain an activation reaction solution, the activation reaction solution is added to the reaction system, and activation reaction is performed at room temperature; after 30-60min of reaction, phenylene polysiloxane-PCL / DMF solution is added to the reaction system, the reaction temperature is increased for esterification reaction, after the reaction is completed, the reaction system is transferred to a dialysis bag, deionized water is used for dialysis, and after dialysis is completed, freeze-drying is performed to obtain an impermeable agent;

[0027] Preferably, in step S2, the mass ratio between the cyclodextrin inclusion compound, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide, and N-hydroxysuccinimide is 1.0-1.5:0.17-0.21:0.1-0.15;

[0028] Preferably, in step S2, the reaction temperature of the esterification reaction is 35-45 DEG C, and the reaction time of the esterification reaction is 18-24h;

[0029] The application further provides a preparation method of the composite particle material for water ecological restoration.

[0030] 1. The montmorillonite is soaked in an aqueous hydrochloric acid solution, taken out, washed with deionized water until neutral, vacuum dried, ground and sieved to obtain the activated montmorillonite;

[0031] 2. The nano-hydroxyapatite is dispersed in anhydrous ethanol, and ultrasonic treatment is performed to obtain a nano-hydroxyapatite dispersion liquid;

[0032] 3. The polyvinyl alcohol is dissolved in deionized water, and Tween-80 is added to obtain an aqueous phase;

[0033] 4. The anti-permeation agent, nano-silicon dioxide and the activated montmorillonite prepared in step 1 are dispersed in dichloromethane, the nano-hydroxyapatite dispersion liquid prepared in step 2 is slowly added, and then mixed uniformly to obtain an oil phase;

[0034] 5. In a constant-temperature water bath, the oil phase is slowly added to the aqueous phase at a volume ratio of 1:2-3, a high-speed shearing emulsifier is started, emulsification is performed at a speed of 3000-4000 rpm for 40 min, the stirring speed is reduced to 200 rpm, the temperature is increased to 45-55 DEG C to volatilize the organic solvent, and after the end, centrifugation is performed, the precipitate is collected, washed with deionized water and anhydrous ethanol, vacuum dried, ground and sieved to obtain the composite particle material.

[0035] The application further provides an application of the composite particle material for water ecological restoration. 2+ The composite particle material for water ecological restoration is applied to water quality purification, and is particularly applied to the adsorption and purification of heavy metal ions Pb

[0036] The application has the following beneficial effects:

[0037] This invention provides a composite particle material for water ecological restoration, its preparation method, and its application. The composite material formed by the cyclodextrin inclusion complex and phenylene polysiloxane-PCL improves the adsorption of harmful substances in the aquatic environment. Through the hydrophilic-hydrophobic interaction between polyvinyl alcohol and phenylene polysiloxane-PCL, a seepage barrier with low permeability and high expansion is formed, giving the composite particle material a high water purification function. At the same time, the seepage barrier performance blocks the migration path of pollutants, forming a closed-loop system of restoration and blockage. In this invention, 2,5-dibromophenol is used as the monomer starting material for phenylene polysiloxane, introducing active groups into the low-activity phenylene polysiloxane. Due to the high reactivity of the phenolic hydroxyl group, tert-butyldimethylchlorosilane is used as a protecting agent. Under imidazole catalysis, the tert-butyldimethylsilyl group forms a stable silyl ether bond (Si-O-Ar) with the phenolic hydroxyl group of 2,5-dibromophenol, protecting the phenolic hydroxyl group from subsequent Grignard and silanization reactions, ensuring reaction specificity and reducing byproducts. Stannous octoate catalyzes the ring-opening of ε-caprolactone, and the ε-caprolactone monomer is linked to the phenylene silicon via an ester bond. After deprotection, phenylene siloxane-PCL block copolymers are formed at the active sites of the siloxane monomers. The rigid segments of phenylene polysiloxane form a skeleton, ensuring the overall structure's compactness and impact resistance. The flexible segments of PCL fill the gaps in the skeleton, eliminating micropores between the rigid skeletons through molecular chain entanglement. The aging resistance of phenylene polysiloxane ensures that the polymer does not degrade or deform in long-term aquatic environments. The interfacial compatibility of PCL enhances the binding force between the polymer and inorganic components (such as nano-SiO2 and montmorillonite) in the composite particles, avoiding structural delamination caused by water flow impact or biological disturbance. In this invention, the anti-seepage agent is covalently linked through the esterification reaction of the phenolic hydroxyl groups on phenylene polysiloxane-PCL and the carboxyl groups in the β-cyclodextrin-aliphatic diacid inclusion complex, forming a complex hydrophilic-hydrophobic amphiphilic network structure. In water, β-cyclodextrin can not only adsorb organic pollutants, but also, the activated montmorillonite has a more porous interlayer structure and an increased number of surface hydroxyl groups, which can enhance the adsorption capacity for heavy metal ions. The surface hydroxyl groups can form hydrogen bonds with the oxygen atoms of phenylene polysiloxane-PCL, improving the binding force between montmorillonite and the anti-seepage agent, preventing component detachment after particle molding. Nano-HAP can be connected through Ca... 2+ It forms insoluble phosphate precipitates with heavy metal ions and forms a dual adsorption-precipitation effect with the physical adsorption of cyclodextrin, thereby increasing the adsorption capacity. Polyvinyl alcohol can form hydrogen bonds with the PCL segments of phenylene polysiloxane-PCL, thereby improving the toughness of the composite particles and preventing the particles from cracking under the impact of water flow. This achieves efficient and long-term barrier against water pollutants and is the core basis for the excellent anti-seepage performance of composite particle materials. Attached Figure Description

[0038] Figure 1Adsorption performance results chart of the composite particle material prepared in the present application examples 1-3 and comparative examples 1-3;

[0039] Figure 2 Impermeable barrier performance results chart of the composite particle material prepared in the present application examples 1-3 and comparative examples 1-3;

[0040] Figure 3 Permeability coefficient results chart of the composite particle material prepared in the present application examples 1-3 and comparative examples 1-3;

[0041] The accompanying drawings are included to provide a further understanding of the present application, and are incorporated in and constitute a part of the specification, illustrate embodiments of the present application and, together with the description, serve to explain the present application, and do not limit the present application. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by one of ordinary skill in the art. In addition, any method and material similar or equivalent to those described herein can be used in the present application. The preferred methods and materials described herein are only used for demonstration, but cannot limit the content of the present application.

[0044] The experimental methods in the following examples are all conventional methods unless otherwise specified. The experimental materials and strains used in the following examples are all purchased from commercial channels unless otherwise specified.

[0045] Example 1

[0046] The present application provides a composite particle material for water ecological restoration, which comprises the following components in parts by weight: impermeable agent 60 parts, montmorillonite 8 parts, nano-hydroxyapatite 10 parts, nano-silicon dioxide 5 parts, polyvinyl alcohol 3 parts.

[0047] The preparation method of the phenylene polysiloxane-PCL specifically includes the following steps:

[0048] A1, 2.5 g of 2,5-dibromophenol was dissolved in 40 mL of anhydrous DMF, and nitrogen was bubbled. 1.4 g of imidazole was added under a nitrogen atmosphere, and stirred until dissolved. 1.8 g of tert-butyldimethylsilyl chloride was dissolved in 10 mL of anhydrous DMF to obtain a tert-butyldimethylsilyl chloride / DMF solution. The tert-butyldimethylsilyl chloride / DMF solution was slowly added to the reaction system at a rate of 0.5 mL / min, and the protection reaction was carried out at room temperature. After 2 h, 70 mL of saturated NaCl aqueous solution was added for washing, and ethyl acetate was added for repeated extraction three times. The organic phase was combined, and the water in the organic phase was dried with anhydrous sodium sulfate. The excess reaction solvent was removed by rotary evaporation to obtain 2,5-dibromophenol-TBDMS;

[0049] A2, magnesium turnings were activated with 0.1 mol / L dilute hydrochloric acid aqueous solution and vacuum dried. 0.6 g of the treated magnesium turnings and 0.1 g of iodine pellets were placed in a three-necked flask, and nitrogen was bubbled. 10 mL of anhydrous THF was added under a nitrogen atmosphere, and stirred until the iodine faded. 2,5-dibromophenol-TBDMS prepared in step A1 was dissolved in 20 mL of anhydrous THF, and added to the three-necked flask at a rate of 1 mL / min. The stirring speed was 180 rpm during the addition. After the addition was completed, the stirring speed was maintained, and the reaction temperature was increased to 40°C. The Grignard reaction was carried out for 1.5 h. After the reaction was completed, 2,5-bis(bromomagnesiumyl) phenoxy-TBDMS reaction solution was obtained.

[0050] A3, the 2,5-bis(bromomagnesiumyl) phenoxy-TBDMS reaction solution prepared in step A2 was cooled in an ice water bath. After cooling to 0°C, 1.8 g of dimethyldiethoxysilane was dissolved in 10 mL of anhydrous THF to obtain a dimethyldiethoxysilane / THF solution. The dimethyldiethoxysilane / THF solution was slowly added to the reaction system at a rate of 0.5 mL / min under a nitrogen atmosphere. After the addition was completed, the pre-reaction was carried out under ice water bath conditions for 1 h. The reaction temperature was increased to room temperature for the silylation reaction, which was carried out for 5 h. After the reaction was completed, saturated NH4Cl aqueous solution at 0°C was added for quenching, and ethyl acetate was added for repeated extraction. The organic phase was combined, and the water in the organic phase was dried with anhydrous sodium sulfate. The excess reaction solvent was removed by rotary evaporation to obtain phenylene siloxane monomer-TBDMS.

[0051] A4, the phenylene polysiloxane-PCL-TBDMS prepared in step A3 was taken 2.0 g and placed in a flask, 30 mL of anhydrous toluene was added, after complete dissolution, ε-caprolactone 4.2 g and stannous octoate 8.4 mg were added, vacuum degassing 3 times and then filled with nitrogen, under the nitrogen atmosphere, the reaction temperature was raised to 120℃, and the polymerization reaction was carried out, the reaction was carried out for 18 h, after the reaction was completed, the reaction system was cooled to room temperature, anhydrous THF was added and stirred until the reactants were completely dissolved, 300 mL of anhydrous methanol cooled to 4℃ was added to the reaction system, and alcohol precipitation treatment was carried out, after repeated treatment for three times, filtration was carried out, the precipitate was collected, washed with 4℃ anhydrous methanol, and then vacuum dried at 60℃ for 8 h to obtain phenylene polysiloxane-PCL-TBDMS;

[0052] A5, the phenylene polysiloxane-PCL-TBDMS prepared in step A4 was dissolved in 20 mL of anhydrous THF, 6 mL of 1 mol / L tetrabutylammonium fluoride / THF solution was added, and the stirring reaction was carried out at room temperature and 300 rpm for 3 h, then the reaction system was poured into 4℃ deionized water, dichloromethane was added for extraction, the organic phase was collected, anhydrous sodium sulfate was added to the organic phase to remove water, the solvent was evaporated, anhydrous methanol was added for alcohol precipitation, the precipitate was collected and vacuum dried to obtain phenylene polysiloxane-PCL;

[0053] The preparation method of the impermeable agent specifically comprises the following steps:

[0054] S1, β-cyclodextrin 6.8 g was placed in deionized water, heated to 70℃, stirred until completely dissolved, then adipic acid 0.85 g was added, the reaction temperature was maintained at 70℃, and the inclusion reaction was carried out, the reaction was carried out for 2 h, after the reaction was completed, the reaction system was naturally cooled to room temperature, and then placed at 4℃ for 12 h, filtered, the filter cake was collected, washed with 4℃ anhydrous ethanol, and then vacuum dried at 60℃ for 8 h to obtain the cyclodextrin inclusion compound;

[0055] S2, the cyclodextrin inclusion compound 1.0 g prepared in step S1 was dissolved in 20 mL of DMF, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide 0.17 g and N-hydroxysuccinimide 0.1 g were dissolved in 30 mL of MES buffer (concentration of 1 mol / L, pH=5.5) to obtain an activation reaction solution, the activation reaction solution was added to the reaction system, and the activation reaction was carried out at room temperature, after 30 min, phenylene polysiloxane-PCL 5.0 g was dissolved in 20 mL of DMF to obtain a phenylene polysiloxane-PCL / DMF solution, the phenylene polysiloxane-PCL / DMF solution was added to the reaction system, the reaction temperature was raised to 35℃, and the esterification reaction was carried out, the reaction was carried out for 24 h, after the reaction was completed, the reaction system was transferred to a dialysis bag, dialyzed with deionized water, after dialysis, freeze-dried to obtain the impermeable agent;

[0056] The embodiment also provides a composite particle material for water ecological restoration and a preparation method thereof, and specifically comprises the following steps:

[0057] ①According to the weight parts, the montmorillonite is soaked in a 0.1 mol / L hydrochloric acid aqueous solution, after soaking for 2 h, it is taken out, washed with deionized water until neutral, and then vacuum dried at 60℃ for 8 h, ground, and sieved through a 200-mesh screen to obtain activated montmorillonite;

[0058] ②According to the weight parts, the nano-hydroxyapatite is dispersed in anhydrous ethanol with a mass concentration of 0.1 g / mL, and then placed in a 500W ultrasonic device for 30 min to obtain a nano-hydroxyapatite dispersion liquid;

[0059] ③According to the weight parts, the polyvinyl alcohol is placed in deionized water, the temperature is increased to 80℃, and the polyvinyl alcohol is stirred until completely dissolved, so that the mass fraction of the polyvinyl alcohol in the water is 0.5%, and then the temperature is cooled to room temperature, Tween-80 is added with a mass fraction of 0.5%, and stirring is performed at a speed of 200 rpm for 10 min to form a uniform aqueous phase;

[0060] ④According to the weight parts, the impermeable agent, nano-silicon dioxide and the activated montmorillonite prepared in step ① are dispersed in dichloromethane, the nano-hydroxyapatite dispersion liquid prepared in step ② is slowly added, stirring is performed at a speed of 300 rpm for 30 min, and then uniformly mixed to obtain an oil phase;

[0061] ⑤In a 30℃ constant-temperature water bath, the oil phase is slowly added to the aqueous phase at a volume ratio of 1:2, a high-speed shearing emulsifier is started, emulsification is performed at a speed of 3000 rpm for 40 min, the stirring speed is then reduced to 200 rpm, the temperature is increased to 45℃ to volatilize the organic solvent, and after the process is completed, centrifugation is performed at 3000 rpm for 15 min, the precipitate is collected, washed with 4℃ deionized water for 3 times, washed with anhydrous ethanol for 1 time, vacuum dried at 60℃ for 6 h, ground and sieved through a 100-mesh screen to obtain the composite particle material.

[0062] Example 2

[0063] The application provides a composite particle material for water ecological restoration, which comprises the following components in parts by weight: an impermeable agent 65 parts, montmorillonite 5 parts, nano-hydroxyapatite 7 parts, nano-silicon dioxide 8 parts, and polyvinyl alcohol 4 parts.

[0064] The preparation method of the phenylene polysiloxane-PCL specifically comprises the following steps:

[0065] A1, 2.5 g of 2,5-dibromophenol was dissolved in 40 mL of anhydrous DMF, and nitrogen was bubbled. 1.6 g of imidazole was added under a nitrogen atmosphere, and stirred until dissolved. 2.0 g of tert-butyldimethylsilyl chloride was dissolved in 10 mL of anhydrous DMF to obtain a tert-butyldimethylsilyl chloride / DMF solution. The tert-butyldimethylsilyl chloride / DMF solution was slowly added to the reaction system at a rate of 0.5 mL / min, and the protection reaction was performed at room temperature. After 2 h, 70 mL of saturated NaCl aqueous solution was added for washing, and ethyl acetate was added for repeated extraction three times. The organic phase was combined, and the water content of the organic phase was dried with anhydrous sodium sulfate. The excess reaction solvent was removed by rotary evaporation to obtain 2,5-dibromophenol-TBDMS;

[0066] A2, magnesium turnings were activated with 0.1 mol / L dilute hydrochloric acid aqueous solution and vacuum dried. 0.5 g of the treated magnesium turnings and 0.1 g of iodine pellets were placed in a three-necked flask, and nitrogen was bubbled. 10 mL of anhydrous THF was added under a nitrogen atmosphere, and stirred until the iodine faded. 2,5-dibromophenol-TBDMS prepared in step A1 was dissolved in 20 mL of anhydrous THF, and added to the three-necked flask at a rate of 1 mL / min. The stirring speed was 180 rpm during the addition. After the addition was completed, the stirring speed was maintained, and the reaction temperature was increased to 45°C. The Grignard reaction was performed for 2 h. After the reaction was completed, 2,5-bis(bromomagnesiumyl) phenoxy-TBDMS reaction solution was obtained.

[0067] A3, the 2,5-bis(bromomagnesiumyl) phenoxy-TBDMS reaction solution prepared in step A2 was cooled in an ice water bath. After cooling to 0°C, 2.2 g of dimethyldiethoxysilane was dissolved in 10 mL of anhydrous THF to obtain a dimethyldiethoxysilane / THF solution. The dimethyldiethoxysilane / THF solution was slowly added to the reaction system at a rate of 0.5 mL / min under a nitrogen atmosphere. After the addition was completed, the pre-reaction was performed under ice water bath conditions for 2 h. The reaction temperature was increased to room temperature, and the silylation reaction was performed for 4 h. After the reaction was completed, saturated NH4Cl aqueous solution at 0°C was added for quenching, and ethyl acetate was added for repeated extraction. The organic phase was combined, and the water content of the organic phase was dried with anhydrous sodium sulfate. The excess reaction solvent was removed by rotary evaporation to obtain phenylene siloxane monomer-TBDMS.

[0068] A4, the phenylene polysiloxane-PCL-TBDMS prepared in step A3 was taken 2.5 g and placed in a flask, 30 mL of anhydrous toluene was added, after complete dissolution, ε-caprolactone 5.4 g and stannous octoate 13 mg were added, vacuum degassing 3 times, then nitrogen was filled, under nitrogen atmosphere, the reaction temperature was raised to 125℃, and the polymerization reaction was carried out, the reaction was carried out for 16 h, after the reaction was completed, the reaction system was cooled to room temperature, anhydrous THF was added and stirred until the reactants were completely dissolved, then 300 mL of anhydrous methanol cooled to 4℃ was added to the reaction system, and alcohol precipitation treatment was carried out, after repeated treatment for three times, filtration was carried out, the precipitate was collected, washed with 4℃ anhydrous methanol, and then vacuum dried at 60℃ for 8 h to obtain phenylene polysiloxane-PCL-TBDMS;

[0069] A5, the phenylene polysiloxane-PCL-TBDMS prepared in step A4 was dissolved in 20 mL of anhydrous THF, 6 mL of 1 mol / L tetrabutylammonium fluoride / THF solution was added, and the stirring reaction was carried out at room temperature at a speed of 400 rpm for 2.5 h, then the reaction system was poured into 4℃ deionized water, dichloromethane was added for extraction, the organic phase was collected, anhydrous sodium sulfate was added to the organic phase to remove water, the solvent was evaporated, anhydrous methanol was added for alcohol precipitation, the precipitate was collected, and vacuum drying was carried out to obtain phenylene polysiloxane-PCL;

[0070] The preparation method of the impermeable agent specifically comprises the following steps:

[0071] S1, β-cyclodextrin 6.8 g was placed in deionized water, heated to 70℃, stirred until completely dissolved, heptanedioic acid 0.95 g was added, the reaction temperature was maintained at 80℃, and the inclusion reaction was carried out for 1 h, after the reaction was completed, the reaction system was naturally cooled to room temperature, and then placed at 4℃ for 12 h, filtered, the filter cake was collected, washed with 4℃ anhydrous ethanol, and then vacuum dried at 60℃ for 8 h to obtain the cyclodextrin inclusion compound;

[0072] S2, the cyclodextrin inclusion compound 1.5 g prepared in step S1 was dissolved in 20 mL of DMF, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide 0.21 g and N-hydroxysuccinimide 0.15 g were dissolved in 30 mL of MES buffer (concentration of 1 mol / L, pH=5.5) to obtain an activation reaction solution, the activation reaction solution was added to the reaction system, and the activation reaction was carried out at room temperature for 30 min, then phenylene polysiloxane-PCL 6.0 g was dissolved in 20 mL of DMF to obtain a phenylene polysiloxane-PCL / DMF solution, the phenylene polysiloxane-PCL / DMF solution was added to the reaction system, the reaction temperature was raised to 40℃, and the esterification reaction was carried out for 21 h, after the reaction was completed, the reaction system was transferred to a dialysis bag, dialyzed with deionized water, and then freeze-dried to obtain the impermeable agent;

[0073] The embodiment also provides a composite particle material for water ecological restoration and a preparation method thereof, and specifically comprises the following steps:

[0074] ①According to the weight parts, the montmorillonite is soaked in a 0.1 mol / L hydrochloric acid aqueous solution, after soaking for 2 h, it is taken out, washed with deionized water until neutral, and then vacuum dried at 60℃ for 8 h, ground, and sieved through a 200-mesh screen to obtain activated montmorillonite;

[0075] ②According to the weight parts, the nano-hydroxyapatite is dispersed in anhydrous ethanol to obtain a nano-hydroxyapatite dispersion liquid with a mass concentration of 0.1 g / mL, and the dispersion liquid is subjected to ultrasonic treatment at 500 W for 30 min;

[0076] ③According to the weight parts, the polyvinyl alcohol is placed in deionized water, the temperature is increased to 80℃, and the polyvinyl alcohol is stirred until completely dissolved, so that the mass fraction of the polyvinyl alcohol in the water is 0.5%, and then the temperature is cooled to room temperature, Tween-80 is added at a mass fraction of 0.5%, and stirring is performed at a speed of 200 rpm for 10 min to form a uniform aqueous phase;

[0077] ④According to the weight parts, the impermeable agent, nano-silicon dioxide and activated montmorillonite prepared in step ① are dispersed in dichloromethane, the nano-hydroxyapatite dispersion liquid prepared in step ② is slowly added, stirring is performed at a speed of 300 rpm for 30 min, and then the mixture is uniformly mixed to obtain an oil phase;

[0078] ⑤In a 30℃ constant-temperature water bath, the oil phase is slowly added to the aqueous phase at a volume ratio of 1:2.5, a high-speed shearing emulsifier is started, emulsification is performed at a speed of 3500 rpm for 40 min, the stirring speed is then reduced to 200 rpm, the temperature is increased to 50℃ to volatilize the organic solvent, and after the process is completed, centrifugation is performed at 3000 rpm for 15 min, the precipitate is collected, washed with 4℃ deionized water for 3 times, washed with anhydrous ethanol for 1 time, vacuum dried at 60℃ for 6 h, ground and sieved through a 100-mesh screen to obtain the composite particle material.

[0079] Example 3

[0080] The present application provides a composite particle material for water ecological restoration, which comprises the following components by weight: 70 parts of an impermeable agent, 7 parts of montmorillonite, 5 parts of nano-hydroxyapatite, 6 parts of nano-silicon dioxide, and 5 parts of polyvinyl alcohol.

[0081] The preparation method of the phenylene polysiloxane-PCL specifically comprises the following steps:

[0082] A1, 2.5 g of 2,5-dibromophenol was dissolved in 40 mL of anhydrous DMF, and nitrogen was bubbled. 1.8 g of imidazole was added under a nitrogen atmosphere, and stirred until dissolved. 2.2 g of tert-butyldimethylsilyl chloride was dissolved in 10 mL of anhydrous DMF to obtain a tert-butyldimethylsilyl chloride / DMF solution. The tert-butyldimethylsilyl chloride / DMF solution was slowly added to the reaction system at a rate of 0.5 mL / min, and the protection reaction was carried out at room temperature. After 2 h, 70 mL of saturated NaCl aqueous solution was added for washing, and ethyl acetate was added for repeated extraction three times. The organic phase was combined, and the water in the organic phase was dried with anhydrous sodium sulfate. The excess reaction solvent was removed by rotary evaporation to obtain 2,5-dibromophenol-TBDMS;

[0083] A2, magnesium turnings were activated with 0.1 mol / L dilute hydrochloric acid aqueous solution and vacuum dried. 0.4 g of the treated magnesium turnings and 0.1 g of iodine pellets were placed in a three-necked flask, and nitrogen was bubbled. 10 mL of anhydrous THF was added under a nitrogen atmosphere, and stirred until the iodine faded. 2,5-dibromophenol-TBDMS prepared in step A1 was dissolved in 20 mL of anhydrous THF, and added to the three-necked flask at a rate of 1 mL / min. The stirring speed was 180 rpm during the addition. After the addition was completed, the stirring speed was maintained, and the reaction temperature was increased to 50°C. The Grignard reaction was carried out for 1 h. After the reaction was completed, 2,5-bis(bromomagnesiumyl) phenoxy-TBDMS reaction solution was obtained.

[0084] A3, the 2,5-bis(bromomagnesiumyl) phenoxy-TBDMS reaction solution prepared in step A2 was cooled in an ice water bath. After cooling to 0°C, 2.4 g of dimethyldiethoxysilane was dissolved in 10 mL of anhydrous THF to obtain a dimethyldiethoxysilane / THF solution. The dimethyldiethoxysilane / THF solution was slowly added to the reaction system at a rate of 0.5 mL / min under a nitrogen atmosphere. After the addition was completed, the pre-reaction was carried out under ice water bath conditions for 3 h. The reaction temperature was increased to room temperature for the silylation reaction. After 3 h, saturated NH4Cl aqueous solution at 0°C was added for quenching reaction. Ethyl acetate was added for repeated extraction. The organic phase was combined, and the water in the organic phase was dried with anhydrous sodium sulfate. The excess reaction solvent was removed by rotary evaporation to obtain phenylene siloxane monomer-TBDMS.

[0085] A4, the phenylene polysiloxane-PCL-TBDMS prepared in step A3 was taken 3.0 g and placed in a flask, 30 mL of anhydrous toluene was added, after complete dissolution, ε-caprolactone 6.5 g and stannous octoate 19.5 mg were added, vacuum degassing 3 times and then filled with nitrogen, under nitrogen atmosphere, the reaction temperature was raised to 130℃, and the polymerization reaction was carried out, the reaction was carried out for 14 h, after the reaction was completed, the reaction system was cooled to room temperature, anhydrous THF was added and stirred until the reactants were completely dissolved, 300 mL of anhydrous methanol cooled to 4℃ was added to the reaction system, and alcohol precipitation treatment was carried out, after repeated treatment for three times, filtration was carried out, the precipitate was collected, washed with 4℃ anhydrous methanol, and then vacuum dried at 60℃ for 8 h to obtain phenylene polysiloxane-PCL-TBDMS;

[0086] A5, the phenylene polysiloxane-PCL-TBDMS prepared in step A4 was dissolved in 20 mL of anhydrous THF, 6 mL of 1 mol / L tetrabutylammonium fluoride / THF solution was added, and the stirring reaction was carried out at room temperature and 500 rpm for 2 h, then the reaction system was poured into 4℃ deionized water, dichloromethane was added for extraction, the organic phase was collected, anhydrous sodium sulfate was added to the organic phase to remove water, the solvent was evaporated, anhydrous methanol was added for alcohol precipitation, the precipitate was collected and vacuum dried to obtain phenylene polysiloxane-PCL;

[0087] The preparation method of the impermeable agent specifically comprises the following steps:

[0088] S1, β-cyclodextrin 6.8 g was placed in deionized water, heated to 70℃, stirred until completely dissolved, then suberic acid 1.0 g was added, the reaction temperature was maintained at 80℃, and the inclusion reaction was carried out, the reaction was carried out for 1.5 h, after the reaction was completed, the reaction system was naturally cooled to room temperature, and then placed at 4℃ for 12 h, filtered, the filter cake was collected, washed with 4℃ anhydrous ethanol, and then vacuum dried at 60℃ for 8 h to obtain the cyclodextrin inclusion compound;

[0089] S2, the cyclodextrin inclusion compound 1.2 g prepared in step S1 was dissolved in 20 mL of DMF, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide 0.19 g and N-hydroxysuccinimide 0.12 g were dissolved in 30 mL of MES buffer (concentration of 1 mol / L, pH=5.5) to obtain an activation reaction solution, the activation reaction solution was added to the reaction system, and the activation reaction was carried out at room temperature, after 30 min, phenylene polysiloxane-PCL 7.2 g was dissolved in 20 mL of DMF to obtain a phenylene polysiloxane-PCL / DMF solution, the phenylene polysiloxane-PCL / DMF solution was added to the reaction system, the reaction temperature was raised to 45℃, and the esterification reaction was carried out, the reaction was carried out for 18 h, after the reaction was completed, the reaction system was transferred to a dialysis bag, dialyzed with deionized water, after dialysis, freeze-dried to obtain the impermeable agent;

[0090] The embodiment also provides a composite particle material for water ecological restoration and a preparation method thereof, and specifically comprises the following steps:

[0091] ①According to the weight parts, the montmorillonite is soaked in a 0.1 mol / L hydrochloric acid aqueous solution, after soaking for 2 h, it is taken out, washed with deionized water until neutral, and then vacuum dried at 60°C for 8 h, ground, and sieved through a 200-mesh screen to obtain activated montmorillonite;

[0092] ②According to the weight parts, the nano-hydroxyapatite is dispersed in anhydrous ethanol to obtain a nano-hydroxyapatite dispersion liquid with a mass concentration of 0.1 g / mL, and then subjected to ultrasonic treatment at 500 W for 30 min;

[0093] ③According to the weight parts, the polyvinyl alcohol is placed in deionized water, the temperature is raised to 80°C, and stirring is performed until the polyvinyl alcohol is completely dissolved, so that the mass fraction of the polyvinyl alcohol in the water is 0.5%, and then the temperature is cooled to room temperature, Tween-80 is added at a mass fraction of 0.5%, and stirring is performed at a speed of 200 rpm for 10 min to form a uniform aqueous phase;

[0094] ④According to the weight parts, the impermeable agent, nano-silicon dioxide, and activated montmorillonite prepared in step ① are dispersed in dichloromethane, the nano-hydroxyapatite dispersion liquid prepared in step ② is slowly added, stirring is performed at a speed of 300 rpm for 30 min, and then uniform mixing is performed to obtain an oil phase;

[0095] ⑤In a 30°C constant-temperature water bath, the oil phase is slowly added to the aqueous phase at a volume ratio of 1:3, a high-speed shearing emulsifier is started, emulsification is performed at a speed of 4000 rpm for 40 min, the stirring speed is then reduced to 200 rpm, the temperature is raised to 55°C to volatilize the organic solvent, and after the process is completed, centrifugation is performed at 3000 rpm for 15 min, the precipitate is collected, washed with 4°C deionized water for 3 times, washed with anhydrous ethanol for 1 time, vacuum dried at 60°C for 6 h, ground, and then sieved through a 100-mesh screen to obtain the composite particle material.

[0096] Comparative Example 1

[0097] The comparative example provides a composite particle material and a preparation method thereof, which are different from the embodiment 1 only in that the sodium-based bentonite is used to replace the impermeable agent in the same weight parts in all components, and the remaining components and component contents are the same as those in the embodiment 1.

[0098] Comparative Example 2

[0099] The comparative example provides a composite particle material and a preparation method thereof, which are different from the embodiment 1 only in that the β-cyclodextrin is used to replace the cyclodextrin inclusion compound in the same weight parts in the component of the impermeable agent, and the benzene-containing polysiloxane-PCL and the cyclodextrin are mixed in the preparation method of the impermeable agent, and the remaining components and component contents are the same as those in the embodiment 1.

[0100] Comparative Example 3

[0101] This comparative example provides a composite particle material and a preparation method thereof, which is only different from Example 1 in that the cyclodextrin inclusion compound is not contained in the component of the impermeable agent, and the remaining components and component contents are the same as those of Example 1.

[0102] Experimental Example 1

[0103] The composite particle materials prepared in Examples 1-3 and Comparative Examples 1-3 were respectively subjected to adsorption performance tests on Pb 2+ , Cd 2+ , Cr 6+ and the organic pollutant bisphenol A:

[0104] Lead nitrate, chromium nitrate and potassium dichromate were dissolved in deionized water and further diluted into a working solution of 50 mg / L. Bisphenol A was dissolved in a small amount of methanol and then diluted with deionized water to prepare a working solution of 50 mg / L. The concentrations of Pb 2+ , Cd 2+ were detected by atomic absorption spectrophotometry, the concentration of Cr 6+ was detected by ultraviolet-visible spectrophotometry, and the concentration of the organic pollutant bisphenol A was detected by high performance liquid chromatography. 0.05 g of the composite particles was placed in a conical flask, 50 mL of the heavy metal ion working solution was added, and after sealing, it was placed in a constant temperature oscillation incubator, oscillated at 25°C and 180 rpm for 24 h. After oscillation, 5 mL of the mixed solution was taken, centrifuged at 5000 rpm for 15 min, and the supernatant was filtered through a 0.45 μm filter membrane for detection. 0.05 g of the composite particle material was accurately weighed into a conical flask, 50 mL of the bisphenol A working solution was added, and the pH was adjusted to 7.0. After sealing, it was placed in a constant temperature oscillation incubator, oscillated at 25°C and 180 rpm for 24 h. After oscillation, 5 mL of the mixed solution was taken, centrifuged at 5000 rpm for 15 min, and the supernatant was filtered through a 0.45 μm filter membrane for detection. After the pollutant concentration was tested, the adsorption capacity (Q e , mg / g) was calculated according to the following formula:

[0105] ;

[0106] Wherein, C0 is the initial concentration of the pollutant (mg / L); C e is the equilibrium concentration (mg / L); V is the solution volume (L); m is the mass of the composite particles (g);

[0107] Figure 1The adsorption performance results of the composite particle materials prepared in Examples 1-3 and Comparative Examples 1-3 of the present application are shown in the figure. The adsorption capacities of Examples 1-3 for different heavy metal ions and organic pollutants are obviously higher than those of Comparative Examples 1, 2 and 3. Among them, the adsorption performance for Pb 2+ is the highest. In the composite particle material, due to the strong ion exchange between Ca 2+ in the nano-hydroxyapatite and Pb 2+ , a more stable Pb3(PO4)2can be formed, so the adsorption performance for Pb 2+ is higher than that for Cd 2+ . In Comparative Example 1, the sodium-based bentonite only has interlayer ion exchange capacity and no hydrophobic cavity of cyclodextrin, so it cannot adsorb bisphenol A, resulting in a sharp drop in the adsorption capacity of bisphenol A. The ion exchange capacity of bentonite is weaker than the synergy of montmorillonite hydroxyapatite, and there is no cyclodextrin coordination adsorption site. The capacities for Pb 2+ , Cd 2+ and Cr 6+ are the lowest. In Comparative Example 2, the pure β-cyclodextrin cannot be included with adipic acid, so it cannot be fixed with the anti-seepage network of phenylene polysiloxane-PCL, and it is easy to fall off from the anti-seepage agent main chain during the oscillation process, resulting in the loss of auxiliary adsorption sites. In Comparative Example 3, the anti-seepage agent only remains phenylene polysiloxane-PCL, and there is no β-cyclodextrin auxiliary adsorption site. The hydrophobic main chain is easy to agglomerate, which can block the adsorption sites of nHAP and activated montmorillonite. Therefore, the adsorption capacity of Comparative Example 3 is lower than that of Comparative Example 2, which proves that the β-cyclodextrin inclusion compound not only provides auxiliary sites, but also can expand the hydrophobic main chain to avoid blocking the adsorption sites.

[0108] Bisphenol A is a small-molecule organic pollutant that matches the cavity of β-cyclodextrin and can enter the cavity to form an inclusion compound through hydrophobic interaction. The adsorption capacity of Examples 1-3 for bisphenol A is the highest. Nano-silicon dioxide can form hydrogen bonds with the anti-seepage agent and montmorillonite through surface hydroxyl groups to avoid agglomeration of each component. If the anti-seepage agent agglomerates, the hydrophobic cavity of β-cyclodextrin will be wrapped inside the agglomerate and cannot contact bisphenol A molecules, resulting in a decrease in effective sites. In Comparative Example 1, sodium-based bentonite does not contain β-cyclodextrin, and only a small amount of bisphenol A is adsorbed by the weak hydrophobic interaction of montmorillonite. In Comparative Example 2, pure β-cyclodextrin is easy to fall off from the anti-seepage agent main chain during the oscillation process, resulting in a decrease in the total amount of β-cyclodextrin actually participating in adsorption. Although a part of the β-cyclodextrin that has not fallen off remains, it is much lower than that of Examples 1-3. In Comparative Example 3, the anti-seepage agent only retains the hydrophobic main chain of phenylene polysiloxane-PCL, and there is no β-cyclodextrin cavity. Only a small amount of bisphenol A is adsorbed by the weak hydrophobic interaction of the main chain.

[0109] Experimental Example 2

[0110] The anti-infiltration effect of the composite particle materials prepared in Examples 1-3 and Comparative Examples 1-3 was determined. In this experimental example, the migration process was simulated according to the direction of upper layer of contaminated water → composite particle layer → sediment layer, and the barrier effect of the materials on Pb 2+ and bisphenol A was evaluated. The migration column was filled from bottom to top with a sediment layer (5 cm), a composite particle layer (10 cm), a quartz sand layer (2 cm), and a simulated contaminated water (10 cm), and the simulated contaminated water was Pb 2+ , bisphenol A working solution with a concentration of 50 mg / L and bisphenol A working solution with a concentration of 20 mg / L, respectively. The infiltration speed of the contaminated water layer was controlled to be 0.5 mL / min by using a peristaltic pump. 5 mL of water sample was taken from the “sampling port below the composite particle layer” or the “sampling port above the sediment layer” at 0 h and 48 h, respectively. The water sample was filtered through a 0.45 μm filter membrane, and the concentrations of Pb2+ and bisphenol A were measured. The barrier rate (R, %) of the pollutants was calculated according to the following formula:

[0111] ;

[0112] Wherein, C 上 is the initial pollutant concentration (mg / L) of the upper layer of contaminated water; C 下 is the pollutant concentration (mg / L) of the sampling port below the particle layer;

[0113] Figure 2 The anti-infiltration barrier performance results of the composite particle materials prepared in Examples 1-3 and Comparative Examples 1-3 are shown in the figure. As shown in the figure, after 48 h, Examples 1-3 all meet the anti-infiltration requirements. The barrier rate of Pb 2+ reached 92-97%, and the barrier rate of bisphenol A reached 90-96%. In Comparative Example 1, the sodium bentonite is a physical anti-infiltration agent. The sodium bentonite does not have the dense siloxane structure of the phenylene polysiloxane-PCL, and the porosity of the particle layer is high, so the water phase pollutants can easily penetrate, and the physical anti-infiltration ability decreases sharply. In Comparative Example 3, the anti-infiltration agent is only the phenylene polysiloxane-PCL BPA, which cannot be adsorbed, and only relies on physical anti-infiltration blocking. However, physical anti-infiltration cannot completely prevent small molecule bisphenol A from penetrating, and the barrier rate decreases. The absence of complexation adsorption of cyclodextrin also causes the barrier rate of Pb 2+ to decrease. In Comparative Example 2, pure β-cyclodextrin is easily detached from the anti-infiltration agent backbone during the 48 h infiltration process, resulting in effective pre-adsorption of bisphenol A in the early stage, but loss of adsorption sites in the later stage, and the barrier rate decreases. The hydrophobic backbone is still partially expanded, and the degree of aggregation is lower than that of Comparative Example 3, and the porosity of the particle layer is smaller.

[0114] Experimental Example 3

[0115] In this experimental example, the anti-infiltration performance of the composite particle materials prepared in Examples 1-3 and Comparative Examples 1-3 was tested by the variable water head permeation test method. The specific experimental method includes:

[0116] (1) Use the boiling method to degas pure water, and the water temperature during the experiment should be 3-4℃ higher than the laboratory temperature;

[0117] (2) Install the ring knife containing the sample into the permeation container, and screw the nut tightly, requiring sealing to prevent water and air leakage. In this experiment, a variable water head device is used to saturate the sample;

[0118] (3) Connect the water inlet of the permeation container with the variable water head pipe, fill the water inlet pipe with pure water in the water supply bottle, and then permeate into the permeator. Open the air vent valve to remove the air at the bottom of the permeation container until no air bubbles are overflowed in the water. Close the water valve, flatten the permeation container, and close the water pipe clamp;

[0119] (4) Fill the variable water head pipe with pure water to a predetermined height, and the water head height is determined according to the loose degree of the sample structure (generally not more than 2m). After the water level is stable, cut off the water source, open the water inlet clamp, and let the water pass through the sample. When water overflows from the water outlet, start to record the initial water head height and initial time in the variable water head pipe, and record the changes of water head and time at predetermined time intervals, and record the water temperature at the water outlet;

[0120] (5) Change the water level in the variable water head pipe into height, and then record the changes of water head and time when the water level is stable. Repeat the experiment 4 times, and when the permeation coefficients determined at different initial water heads are within the allowable difference range, the experiment is ended.

[0121] The permeation coefficient (k 20 ) is calculated according to the following formula when the water temperature is 20℃:

[0122]

[0123] k 20 represents the permeation coefficient of the sample at standard temperature (20℃) (cm / s); the constant 2.3 represents the conversion factor of ln and log; a represents the cross-sectional area of the variable water head pipe (cm 2 ), which is taken as a=0.2240cm 2 in this experiment; L represents the permeation path, that is, the sample height (cm), which is 4cm in this experiment; A represents the cross-sectional area of the sample (cm 2 ), which is 29.9962cm 2 because the inner diameter of the ring knife used in this experiment is 6.18cm; t represents the duration (s); η t / η 20 represents the ratio of the dynamic viscosity coefficient of water at T℃ to that at standard temperature; H1 and H2 represent the initial and final water heads (cm);

[0124] Figure 3 The permeation coefficient results of the composite particle materials prepared in Examples 1-3 and Comparative Examples 1-3 of the present application are shown in the graph, and the permeation coefficient k20 The essence is the rate of water or pollutant solution through the pores of the material, which depends on the size and connectivity of the pores: the smaller the pores, the worse the connectivity, the greater the water flow resistance, and the lower the k 20 In Examples 1-3, the permeation performance remains at the order of 10 -9 In Comparative Example 1, the sodium-based bentonite is used to replace the impermeable agent, and the sodium-based bentonite is not activated by hydrochloric acid. The layered structure is dense and cannot effectively fill the pores. Millimeter-micron level connected pores are formed inside the material, and water flows easily and quickly through them, so k 20 is the highest. In Comparative Example 2, pure β-cyclodextrin is used to replace the cyclodextrin inclusion compound. During the 4 repeated permeation tests (long-term flushing of water), it is easy to fall off from the main chain, resulting in local agglomeration of the hydrophobic main chain, forming nanometer-micron level micropores, resulting in an increase in the permeation coefficient. In Comparative Example 3, the impermeable agent does not contain a cyclodextrin inclusion compound, only the phenylene polysiloxane-PCL hydrophobic main chain is retained. Agglomeration causes activated montmorillonite to fail to embed into the main chain gap, physical filling fails, and the connectivity of the pores is greatly improved. Water flows easily through the agglomerated pores, so k 20 is higher.

[0125] Experimental Example 4

[0126] Biological toxicity tests were conducted on the composite particle materials prepared in Examples 1-3 and Comparative Examples 1-3. The biological toxicity test objects included bacteria (Escherichia coli, Bacillus subtilis, and photosynthetic bacteria), aquatic plants (Acorus calamus), and aquatic animals (zebrafish). The specific test methods are as follows:

[0127] 1. Bacterial biological toxicity test: The composite particle material was weighed, and a concentration gradient was prepared using the corresponding culture medium: 0 (blank control), 0.1, 1.0, 5.0, and 10.0 g / L. Ultrasonic treatment was performed for 30 min (500 W) to ensure uniform dispersion of the particles. The particles were removed by passing through a 0.22 μm filter membrane, and only the possible dissolved toxic substances were retained. Each bacterial strain was inoculated into the corresponding culture medium and cultured to the logarithmic phase. In a 96-well plate, 180 μL of the particle suspension and 20 μL of the bacterial solution (bacterial solution concentration 1 × 10 6 CFU / mL) were added to each well. The culture conditions were followed, and after 24 h of culture, the OD600 value was measured. The growth inhibition rate (IR, %) was calculated according to the following formula:

[0128] ;

[0129] 2. Aquatic plant biological toxicity test: The composite particle material was mixed with the sediment at a concentration gradient of 0 (control), 0.5, 1.0, and 2.0 g / kg dry mud. A flowerpot was filled with 100 g of sediment containing the composite particle material, and water was added to a height of 3 cm above the mud surface. One Acorus calamus tuber (with the bud facing up) was planted in each pot, and the experiment was repeated three times. The plants were cultured at 25°C under light. After 28 days, the fresh weight was measured, and the growth inhibition rate (%) was calculated.

[0130] 3. The acute toxicity test was used to observe the mortality and abnormal behavior (such as slow swimming and imbalance) of zebra fish within 96 hours, to evaluate the toxicity of the material to higher aquatic animals. The composite particle material was dispersed in exposure liquid (tap water aerated for 24 hours, pH 7.0±0.5, hardness 50-100 mg / L CaCO3) by ultrasonic dispersion for 30 minutes, and then the supernatant was taken after standing for 1 hour. 8 L of exposure liquid was added to each tank, 10 zebra fish were placed in each tank, the temperature was 25℃±1℃, the light-dark ratio was 12h:12h, the exposure liquid was continuously slightly aerated, and the fish were not fed. 50% of the exposure liquid was replaced every day, and the mortality was observed and recorded every 24 hours.

[0131] The biological toxicity results of the composite particle materials prepared in Examples 1-3 and Comparative Examples 1-3 are shown in the following table. The growth inhibition rates of the examples and comparative example 1 on bacteria and aquatic plants were less than 10%, and the mortality of zebra fish in comparative example 1 was as high as 50%. In comparative example 1, the bentonite may contain free Na⁺, which causes osmotic pressure disorder in zebra fish, resulting in a significantly higher mortality.

[0132]

[0133] Although the embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and alterations can be made thereto without departing from the principles and spirit of the present application.

[0134] The above description of the present application and its embodiments is not restrictive, and the embodiments shown in the drawings are only one of the embodiments of the present application, and the actual application is not limited thereto. In summary, if a person of ordinary skill in the art is inspired by it, without departing from the purpose of the present application, without creative design, similar ways and embodiments of the technical solution can be designed, which should belong to the protection scope of the present application.

Claims

1. A composite particle material for water ecological restoration, characterized in that: The composite particle material comprises the following components in parts by weight: 60-70 parts of anti-seepage agent, 5-8 parts of montmorillonite, 5-10 parts of nano-hydroxyapatite, 5-8 parts of nano-silica, and 3-5 parts of polyvinyl alcohol; the raw materials for preparing the anti-seepage agent are composed of the following components in parts by weight: 5-7.2 parts of phenylene polysiloxane-PCL and 1-1.5 parts of cyclodextrin inclusion complex; The preparation method of the phenylene polysiloxane-PCL specifically includes the following steps: A1. Dissolve 2,5-dibromophenol in anhydrous DMF, purge with flowing nitrogen, add imidazole and stir until dissolved, then slowly add tert-butyldimethylchlorosilane / DMF solution to the reaction system. Perform a protective reaction at room temperature. After the reaction is complete, wash with saturated NaCl aqueous solution, extract repeatedly with ethyl acetate, combine the organic phases, dry the organic phase with anhydrous sodium sulfate, and remove excess reaction solvent by rotary evaporation to obtain 2,5-dibromophenol-TBDMS. A2. Place magnesium shavings and iodine granules in a flask. Under a nitrogen atmosphere, add anhydrous THF and stir until the iodine decolorizes. Then, dissolve the 2,5-dibromophenol-TBDMS prepared in step A1 in anhydrous THF and slowly add it dropwise to the reaction system. After the addition is complete, raise the reaction temperature to carry out the Grignard reaction. After the reaction is completed, 2,5-bis(magnesium bromide)phenoxy-TBDMS reaction solution is obtained. A3. The 2,5-bis(magnesium bromide)phenoxy-TBDMS reaction solution prepared in step A2 was placed in an ice-water bath for cooling. After cooling to 0°C, dimethyldiethoxysilane / THF solution was slowly added dropwise under a nitrogen atmosphere. After the addition was complete, the ice-water bath conditions were maintained for pre-reaction. After reacting for 1-2 hours, the reaction temperature was raised to room temperature for silanization reaction. After reacting for 3-5 hours, saturated NH4Cl aqueous solution at 0°C was added for quenching reaction. Ethyl acetate was added for repeated extraction. The organic phases were combined, and the water in the organic phase was dried with anhydrous sodium sulfate. Excess reaction solvent was removed by rotary evaporation to obtain phenylenesiloxane monomer-TBDMS. A4. Dissolve the phenylene siloxane monomer-TBDMS prepared in step A3 in anhydrous toluene, add ε-caprolactone and stannous octoate, degas under vacuum three times, then purge with nitrogen, raise the reaction temperature to carry out the polymerization reaction, after the reaction is completed, cool, add THF to dissolve the reactants, add anhydrous methanol at 4℃ to carry out alcohol precipitation reaction, filter, collect the precipitate, and dry under vacuum to obtain phenylene polysiloxane-PCL-TBDMS; A5. Dissolve the phenylene polysiloxane-PCL-TBDMS prepared in step A4 in anhydrous THF, add tetrabutylammonium fluoride solution, stir at 300-500 rpm for 2-3 hours at room temperature, pour the reaction system into deionized water at 4℃, add dichloromethane for extraction, collect the organic phase, remove water from the organic phase with anhydrous sodium sulfate, evaporate the solvent, add anhydrous methanol for alcohol precipitation, collect the precipitate, and dry under vacuum to obtain phenylene polysiloxane-PCL. The preparation method of the impermeable agent specifically includes the following steps: S1. Place β-cyclodextrin in deionized water, heat and stir until completely dissolved, add aliphatic diacid, maintain the reaction temperature for inclusion reaction, after the reaction is completed, cool, let stand at 4℃, filter, collect filter cake, wash repeatedly with anhydrous ethanol at 4℃, and vacuum dry to obtain cyclodextrin inclusion complex. S2. Dissolve the cyclodextrin inclusion complex prepared in step S1 in DMF. Dissolve 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide in MES buffer to obtain an activation reaction solution. Add the activation reaction solution to the reaction system and carry out the activation reaction at room temperature. After reacting for 30-60 min, add the phenylene polysiloxane-PCL / DMF solution to the reaction system and raise the reaction temperature to carry out the esterification reaction. After the reaction is completed, transfer the reaction system to a dialysis bag and dialyze with deionized water. After dialysis, freeze-dry to obtain the anti-permeability agent. The preparation method of the composite particle material specifically includes the following steps: ① Soak montmorillonite in hydrochloric acid solution, remove it, wash it with deionized water until neutral, vacuum dry it, grind it and sieve it to obtain activated montmorillonite; ② Disperse nano-hydroxyapatite in anhydrous ethanol, and after ultrasonic treatment, obtain nano-hydroxyapatite dispersion; ③ Dissolve polyvinyl alcohol in deionized water, add Tween-80, and obtain the aqueous phase; ④ Take the anti-seepage agent, nano silica and the activated montmorillonite prepared in step ① and disperse them in dichloromethane. Slowly add the nano hydroxyapatite dispersion prepared in step ② and mix evenly to obtain the oil phase. ⑤ In a constant temperature water bath, the oil phase is slowly added to the aqueous phase at a volume ratio of 1:2-3. The high-speed shear emulsifier is turned on and emulsified at a speed of 3000-4000 rpm for 40 minutes. Then, the stirring speed is reduced to 200 rpm and the temperature is increased to 45-55℃ to allow the organic solvent to evaporate. After the process is completed, the mixture is centrifuged, the precipitate is collected, washed with deionized water and anhydrous ethanol, vacuum dried, ground, and sieved to obtain the composite particle material.

2. The composite particle material for water ecological restoration according to claim 1, characterized in that: In step A1, the mass ratio of 2,5-dibromophenol to imidazole is 2.5:1.4-1.8; the mass ratio of 2,5-dibromophenol to tert-butyldimethylchlorosilane is 2.5:1.8-2.

2.

3. The composite particle material for water ecological restoration according to claim 2, characterized in that: In step A2, the mass ratio of magnesium shavings to iodine granules is 4-6:1; the mass ratio of magnesium shavings to 2,5-dibromophenol in step A1 is 0.4-0.6:2.5; the Grignard reaction temperature is 40-50℃, and the Grignard reaction time is 1-2 hours.

4. The composite particle material for water ecological restoration according to claim 3, characterized in that: In step A3, the mass ratio of the dimethyldiethoxysilane to the 2,5-dibromophenol in step A1 is 1.8-2.4:2.

5.

5. The composite particle material for water ecological restoration according to claim 4, characterized in that: In step A4, the mass ratio of the phenylenesiloxane monomer-TBDMS to ε-caprolactone is 2.0-3.0:4.2-6.5; the added mass of stannous octoate is 0.2%-0.3% of the mass of ε-caprolactone; the polymerization temperature is 120-130℃, the polymerization time is 14-18h, and the polymerization stirring speed is 300-400rpm.

6. The composite particle material for water ecological restoration according to claim 5, characterized in that: In step S1, the aliphatic diacid includes at least one of adipic acid, pimelic acid, octanoic acid, and azelaic acid; the mass ratio between the β-cyclodextrin and the aliphatic diacid is 6.8:0.85-1.0; the reaction temperature of the inclusion reaction is 70-80℃, and the reaction time of the inclusion reaction is 1-2h; In step S2, the mass ratio of the cyclodextrin inclusion complex to 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide is 1.0-1.5:0.17-0.21:0.1-0.15; the esterification reaction temperature is 35-45℃, and the esterification reaction time is 18-24h.

7. The application of a composite particle material for water ecological restoration according to any one of claims 1-6, characterized in that: The composite particle material was applied to the heavy metal ion Pb 2+ Adsorption and purification of bisphenol A.

Images