Hydrated polymer adsorbent based on saponin embryo modification as well as preparation method and application of hydrated polymer adsorbent

Abstract

The invention discloses a hydrated polymer adsorbent based on saponin embryo modification as well as a preparation method and application thereof, and belongs to the technical field of environmental functional materials. The adsorbent is a three-dimensional network structure material which is prepared by acylating and modifying saponin embryos through maleic anhydride, then carrying out graft copolymerization on the modified saponin embryos, diacetone acrylamide and glycidyl methacrylate, and carrying out crosslinking through N, N-dianilino tetrahydrofuran. The preparation method mainly comprises the following steps: firstly, carrying out acylation reaction on saponin seed embryo dispersion liquid and maleic anhydride under an alkaline condition to obtain acylated saponin seed embryos; then carrying out graft copolymerization with two functional monomers in a hydrogen peroxide-acetylacetone initiation system, and finally adding a cross-linking agent to complete a cross-linking reaction. The molecular chain of the prepared adsorbent is rich in various functional groups such as acylamino, carboxyl and epoxy group, and the adsorbent has efficient adsorption capacity on heavy metal ions and oil pollutants in water, and is large in adsorption capacity and good in stability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of environmental functional materials, and particularly relates to a high-efficiency adsorbent taking natural biomass as a raw material, and particularly relates to a hydrated high-molecular adsorbent based on modified Ginkgo biloba L. seeds and a preparation method thereof, and application of the hydrated high-molecular adsorbent in treatment of wastewater containing heavy metal ions and organic pollutants. BACKGROUND

[0002] With the rapid development of industrialization, the problem of water body heavy metal pollution (such as Pb² + , Cu² + , Cd² + ) and organic pollution (such as oil and dye) is increasingly serious. The adsorption method is widely used due to its simple operation and high efficiency. The commonly used adsorbents include activated carbon, ion exchange resin, synthetic polymer flocculants and the like.

[0003] However, these adsorbents have some limitations: the activated carbon has limited adsorption capacity and is difficult to regenerate; the ion exchange resin is high in cost; and some synthetic polymer flocculants have poor environmental compatibility and may have the risk of secondary pollution. In addition, the development of low-cost, high-adsorption-capacity and biodegradable green adsorbents has become a hot spot of current research.

[0004] Ginkgo biloba L. seeds as a kind of abundant agricultural waste, the main components of which are protein and polysaccharide, and the molecular chain is rich in active groups such as hydroxyl and amino groups, which has the potential to be used as an adsorbent substrate. However, the natural Ginkgo biloba L. seeds have the problems of low adsorption capacity, poor selectivity and easy swelling and loss in water body when directly used. Therefore, how to efficiently modify the Ginkgo biloba L. seeds through molecular design, introduce specific functional groups and construct a stable three-dimensional network structure, so as to prepare a high-performance biomass adsorbent, is a key technical problem to be solved by the present application. SUMMARY

[0005] The primary purpose of the present application is to overcome the shortcomings of the prior art, and to provide a hydrated high-molecular adsorbent which is excellent in adsorption performance, environmentally friendly and low in cost.

[0006] The second purpose of the present application is to provide a preparation method of the above-mentioned hydrated high-molecular adsorbent, which is simple in process, mild in conditions and easy to scale up.

[0007] The third purpose of the present application is to clarify the application of the above-mentioned hydrated high-molecular adsorbent in wastewater treatment, and particularly the excellent performance in deep removal of heavy metal ions and oil pollutants.

[0008] The first aspect of the present application provides a hydrated high molecular adsorbent, which is a three-dimensional network structure material prepared by acylating modification of Ginkgo biloba L. seeds with maleic anhydride, followed by graft copolymerization with diacetone acrylamide and glycidyl methacrylate, and crosslinking with N,N-bis anilino tetrahydrofuran; the molecular chain of the adsorbent is rich in amide, carboxyl and epoxy functional groups.

[0009] The first aspect of the present application provides a method for preparing the hydrated high molecular adsorbent, comprising the following steps: S10, acylating modification of Ginkgo biloba L. seeds: adjust the Ginkgo biloba L. seed dispersion to alkaline pH, add maleic anhydride accounting for 10%-40% of the mass of the Ginkgo biloba L. seeds at 40℃±5℃, maintain the pH value of the system constant during the reaction, and after the reaction is completed, dialysis and freeze-drying are performed to obtain acylated Ginkgo biloba L. seeds; S20, graft copolymerization and crosslinking reaction: disperse the acylated Ginkgo biloba L. seeds obtained in step S10 in water, adjust the pH to 4-5, heat to 50℃±5℃, add an initiator solution composed of hydrogen peroxide and acetylacetone, and simultaneously drop the mixed monomers of diacetone acrylamide aqueous solution and glycidyl methacrylate for graft copolymerization reaction, after the reaction is completed, add N,N-bis anilino tetrahydrofuran crosslinking agent and sodium dodecyl sulfate, heat to 80℃±5℃ for crosslinking reaction to obtain the hydrated high molecular adsorbent.

[0010] In the second aspect of the present application, as a preferred embodiment, in step S10, the mass concentration of the Ginkgo biloba L. seed dispersion is 3%, which is prepared by uniformly stirring 3g of Ginkgo biloba L. seed powder with 197g of water for 10 minutes.

[0011] In the second aspect of the present application, as a preferred embodiment, in step S10, the pH of the dispersion is adjusted to 9.0 using 1 mol / L sodium hydroxide solution, and the pH value is maintained for the acylation reaction, and the reaction time is 90 minutes.

[0012] In the second aspect of the present application, as a preferred embodiment, in step S20, in the initiator solution, hydrogen peroxide is a 30% concentration aqueous solution, and the mass ratio of hydrogen peroxide to acetylacetone is 2:1.

[0013] In the second aspect of the present application, as a preferred embodiment, in step S20, the diacetone acrylamide is added in the form of a 40% concentration aqueous solution, and the mass ratio of diacetone acrylamide to glycidyl methacrylate is between 0.7:1 and 1.2:1.

[0014] In the second aspect of the present application, as a preferred embodiment, in step S20, the total mass ratio of the acylated Gleditsia sinensis seeds to the mixed monomers is between 1:0.28 and 1:0.65.

[0015] In the second aspect of the present application, as a preferred embodiment, in step S20, the graft copolymerization reaction is carried out at 50°C for 3 hours, and the crosslinking reaction is carried out at 80°C for 1 hour.

[0016] The third aspect of the present application is to provide an application of the hydrated high molecular adsorbent in treating oily wastewater or emulsified oil.

[0017] In the third aspect of the present application, as a preferred embodiment, the heavy metal ions include Pb 2+ , Cu 2+ or Cd 2+ .

[0018] Compared with the prior art, the present application has the following beneficial effects: 1) Raw materials are green and renewable, and high-value utilization is achieved: The present application uses Gleditsia sinensis seeds, an agricultural byproduct or waste, as raw materials, which are widely available and low in cost. Not only does this effectively reduce the production cost of the adsorbent, but it also achieves high-value utilization of natural renewable resources, in line with green chemistry and sustainable development strategies, and has significant environmental and economic benefits.

[0019] 2) Synergistic and efficient modification mechanism greatly improves material performance: The present application realizes precise regulation and functional enhancement of the protein structure of Gleditsia sinensis seeds through the two-step strategy of acylation modification and graft copolymerization-crosslinking: Acylation modification: The use of maleic anhydride introduces hydrophilic and active functional groups such as carboxyl groups onto the protein chain, effectively disrupting the tight higher structure of the protein, increasing its solubility and accessibility in water, and providing more active sites for subsequent grafting reactions. Graft copolymerization: Using diacetone acrylamide and glycidyl methacrylate as mixed monomers, diacetone acrylamide provides amide bonds, enhancing the adsorbent's adsorption versatility for different pollutants; and the epoxy groups of glycidyl methacrylate have high reactivity, which can react with the groups on the protein chain and participate in subsequent crosslinking, greatly enriching the three-dimensional network structure of the polymer.

[0020] 3) Excellent adsorption performance of the product, broad application prospects: The three-dimensional network structure of the present application provides a large specific surface area and abundant pores, while introducing various active functional groups such as amide, carboxyl, and epoxy groups, which can efficiently capture heavy metal ions and organic pollutants through coordination, ion exchange, hydrogen bonding, and other mechanisms, with high adsorption capacity and fast adsorption rate.

[0021] 4) Environmentally friendly, low risk of secondary pollution: the main raw material of the application is biomass, and the product itself has good biocompatibility and biodegradability. The synthesis process is carried out in aqueous phase, avoiding the use of a large amount of organic solvent, and the unreacted small molecules are effectively removed by dialysis, reducing the biological toxicity of the product and the potential secondary pollution risk to the environment. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 Synthesis route map of the adsorbent of the application; Figure 2 Adsorbents of examples 1-4 of the application and market comparison samples under different dosing amounts Oilfield produced water oil removal effect comparison chart; Figure 2 Adsorbents of examples 1-4 of the application and market comparison samples under different dosing amounts Oilfield produced water oil removal effect comparison chart; Figure 3 Adsorbents of examples 1-4 of the application and market comparison samples under different temperatures Oilfield produced water oil removal effect comparison chart; Figure 4 Adsorbents of examples 1-4 of the application and market comparison samples under different pH Heavy metal ion adsorption performance comparison chart; Figure 5 Adsorbents of examples 1-4 of the application and market comparison samples under different dosing amounts Heavy metal ion adsorption performance comparison chart; Figure 6 Adsorbents of examples 1-4 of the application and market comparison samples under different initial concentrations Heavy metal ion adsorption performance comparison chart. DETAILED DESCRIPTION

[0023] The application will be further described below in conjunction with the drawings and specific embodiments. It should be noted that the following described embodiments or technical features can be combined in any manner to form new embodiments, provided that there is no conflict. Unless otherwise specified, the materials and equipment used in the embodiments can be purchased from the market. The embodiments described below by reference to the drawings are exemplary and are used to explain the application, and cannot be understood as limiting the application.

[0024] The first aspect of the application is to provide a hydrated high molecular adsorbent, which is a three-dimensional network structure material obtained by acylating modification of Ginkgo biloba seed embryos with maleic anhydride, then grafting copolymerization with diacetone acrylamide and glycidyl methacrylate, and crosslinking with N,N-bis aniline tetrahydrofuran; the molecular chain of the adsorbent is rich in amide, carboxyl and epoxy functional groups.

[0025] Building upon the aforementioned approach, this invention ensures the adsorbent's insolubility in water and structural stability through a cross-linked network, avoiding the swelling and loss issues common with direct use of natural polymers. This makes the material suitable for dynamic water treatment environments and eliminates the risk of secondary dissolution and contamination. The simultaneous presence of amide, carboxyl, and epoxy groups on the molecular chain endows it with multiple adsorption mechanisms. Carboxyl groups can efficiently capture heavy metal ions through ion exchange and coordination; amide groups can adsorb organic pollutants through hydrogen bonding; and epoxy groups provide reactive sites and enhance the material's hydrophilicity and adsorption capacity for specific pollutants. This complementary effect of functional groups gives the adsorbent broad-spectrum adsorption adaptability and high adsorption capacity.

[0026] The first aspect of this invention is to provide a method for preparing the hydrated polymer adsorbent, comprising the following steps: S10. Acylation modification of soapberry seed embryos: The soapberry seed embryo dispersion was adjusted to alkaline pH, and maleic anhydride of 10%-40% of the soapberry seed embryo mass was added at 40℃±5℃ to carry out the reaction. The pH value of the system was kept constant during the reaction. After the reaction was completed, the acylated soapberry seed embryos were obtained by dialysis and freeze drying. S20. Graft copolymerization and crosslinking reaction: The acylated saponin seed embryos obtained in step S10 are dispersed in water, the pH is adjusted to 4-5, the temperature is raised to 50℃±5℃, an initiator solution composed of hydrogen peroxide and acetylacetone is added, and a mixed monomer of diacetone acrylamide aqueous solution and glycidyl methacrylate is added dropwise to carry out a graft copolymerization reaction. After the reaction is completed, N,N-bisphenylaminotetrahydrofuran crosslinking agent and sodium dodecyl sulfate are added, and the temperature is raised to 80℃±5℃ to carry out a crosslinking reaction to obtain the hydrated polymer adsorbent.

[0027] Based on the above scheme, this invention achieves precise regulation and functional enhancement of the structure of saponin embryo protein through a two-step strategy of acylation modification and graft copolymerization-crosslinking: Acylation modification: By using maleic anhydride to introduce hydrophilic and active functional groups such as carboxyl groups into the protein chain, not only is the tight higher-order structure of the protein effectively disrupted, but its solubility and accessibility in water are also improved, providing more active sites for subsequent grafting reactions.

[0028] Graft copolymerization: Diacetone acrylamide and glycidyl methacrylate were selected as mixed monomers. Diacetone acrylamide provided amide bonds, which enhanced the adsorbent's universality for adsorbing different pollutants. Meanwhile, the epoxy groups of glycidyl methacrylate have high reactivity, which can react with groups on protein chains and participate in subsequent cross-linking, greatly enriching the three-dimensional network structure of the polymer.

[0029] The synthetic route diagram of the present invention is as follows: Figure 1As shown, the following is a detailed explanation of each step: Starting material: Soapberry seed embryo. As a natural polymer material, soapberry seed embryo mainly contains biological macromolecules such as proteins and polysaccharides. Its molecular chain is rich in active groups, such as hydroxyl (-OH) and amino (-NH2). These groups are the basis and prerequisite for subsequent chemical modification.

[0030] S10, Acylation Modification: Reagent for reaction: maleic anhydride.

[0031] Reaction mechanism: Under weakly alkaline and mild temperature conditions, the -OH or -NH2 nuclei on the molecular chain of soapberry seed embryo attack the carbonyl carbon in maleic anhydride molecule, causing the anhydride ring to open and undergo an acylation reaction.

[0032] Product characteristics: Acylated saponin seed embryos are generated. This process successfully introduces two crucial functional groups into the biomass framework: Carboxyl group (-COOH): greatly enhances the hydrophilicity and ion exchange capacity of the product, providing sites for subsequent adsorption of heavy metal ions.

[0033] Carbon-carbon double bonds (-CH=CH-): provide polymerization sites for the second-step graft copolymerization reaction.

[0034] S20: Graft copolymerization and crosslinking reaction Grafting and co-gathering: Initiation system: Hydrogen peroxide-acetylacetone is used. This redox initiation system can efficiently generate free radicals under mild conditions to initiate polymerization.

[0035] Functional monomers: Diacetone acrylamide (DAAM): Provides abundant amide groups (-CONH-), which can effectively adsorb organic pollutants through hydrogen bonding and other interactions. Glycidyl methacrylate (GMA): Its key epoxy groups have high reactivity and are the core of constructing the three-dimensional network.

[0036] Product characteristics: A graft copolymer is obtained. At this time, the polymer chain is based on the soapberry seed embryo, on which copolymer side chains composed of DAAM and GMA are grafted, and the ends of the side chains have active epoxy groups.

[0037] Crosslinking reaction: Crosslinking agent: N,N-bisphenylaminotetrahydrofuran.

[0038] Reaction mechanism: Under heating conditions, the active groups on the crosslinking agent molecules undergo a ring-opening reaction with the epoxy groups on the side chains of the graft copolymer, forming a strong chemical bridge between different polymer chains.

[0039] Final product characteristics: A hydrated polymeric adsorbent forming a three-dimensional network structure. This cross-linked network structure endows the material with the following excellent properties: Insoluble: To prevent dissolution during use and ensure structural integrity.

[0040] High specific surface area and porosity: provide ample space and channels for pollutant adsorption.

[0041] Mechanical stability: gives the material good mechanical strength.

[0042] In a preferred embodiment, in step S10, the mass concentration of the soapberry seed embryo dispersion is 3%, which is prepared by stirring 3g of soapberry seed embryo powder with 197g of water at a constant speed for 10 minutes.

[0043] In a preferred embodiment, in step S10, the pH of the dispersion is adjusted to 9.0 using a 1 mol / L sodium hydroxide solution, and the acylation reaction is carried out while maintaining this pH value for 90 minutes.

[0044] In a preferred embodiment, in step S20, the initiator solution contains a 30% aqueous solution of hydrogen peroxide, with a mass ratio of 2:1 to acetylacetone.

[0045] In a preferred embodiment, in step S20, the diacetone acrylamide is added in the form of a 40% aqueous solution, the mass ratio of which to glycidyl methacrylate is between 0.7:1 and 1.2:1.

[0046] Based on the above scheme, experimental verification showed that when the mass ratio of diacetone acrylamide (pure) to glycidyl methacrylate is within the range of 0.7:1 to 1.2:1, the two functional monomers can form a highly efficient graft copolymerization system with acylated saponin seed embryos. The amide groups provided by diacetone acrylamide and the epoxy groups provided by glycidyl methacrylate can be evenly distributed in the molecular chain, ensuring both grafting rate and preventing monomer aggregation. The final product has a stable three-dimensional network structure and sufficient functional group activity. Examples 1-4 all verified its adsorption performance for heavy metal ions and oil pollutants within this range, with an oil removal rate of over 92.2% and a heavy metal removal rate of over 90%, significantly better than similar products on the market.

[0047] In a preferred embodiment, in step S20, the total mass ratio of the acylated saponin seed embryo to the mixed monomers (the total mass of pure diacetone acrylamide and glycidyl methacrylate) is between 1:0.28 and 1:0.65.

[0048] Based on the above scheme, the mass ratio of acylated saponin seed embryos to mixed monomers is a key parameter affecting grafting density and network structure. Experimental verification shows that when the ratio is in the range of 1:0.28 to 1:0.65, the mixed monomers can fully utilize the active sites (carbon-carbon double bonds) on the surface of the acylated saponin seed embryos for grafting, without excessive cross-linking or product aggregation due to excess monomers. Even at a ratio as low as 1:0.28 (as in Examples 1, 3, and 4), the product still possesses abundant amide, carboxyl, and epoxy groups, exhibiting superior adsorption performance compared to market-comparative samples. When the ratio is between 1:0.4 and 1:0.65 (as in Example 2), the grafting density is higher, the three-dimensional network is more compact, and the adsorption capacity is further improved. This range can meet the needs of different application scenarios, combining performance and economy.

[0049] In a preferred embodiment, in step S20, the graft copolymerization reaction is carried out at 50°C for 3 hours, and the crosslinking reaction is carried out at 80°C for 1 hour.

[0050] A third aspect of the present invention is to provide the application of the hydrated polymer adsorbent described above in the treatment of oily wastewater or emulsified oil.

[0051] In a preferred embodiment, the heavy metal ions include Pb. 2+ Cu 2+ or Cd 2+ .

[0052] The following are some embodiments listed in this application, which further illustrate this application.

[0053] Example 1 A method for preparing a hydrated polymeric adsorbent based on modified soapberry seed embryos includes the following preparation steps: S10, Acylation modification of soapberry seed embryos: 200 g of 3% saponin seed embryo dispersion was added to a three-necked flask equipped with a mechanical stirrer, thermometer, and reflux condenser. The pH of the dispersion was adjusted to 9.0 with 1 mol / L sodium hydroxide solution, and the hydration reaction was carried out for 50 min. Under the condition of reaction temperature of 40℃ and continuous stirring, 10% maleic anhydride (based on the mass of saponin seed embryo) was slowly added dropwise. During the reaction, the pH of the system was maintained constant using 1 mol / L sodium hydroxide solution, and the reaction was continued for 90 min. After the reaction was completed, the reaction system was immediately placed in an ice-water bath to terminate the reaction. Then, the mixture was placed in a dialysis bag with a molecular weight cutoff of 7 kDa and dialyzed for 72 hours to completely remove unreacted maleic anhydride and by-product salt ions. Finally, the dialyzed product was freeze-dried to obtain loose and porous acylated saponin seed embryos.

[0054] S20, graft copolymerization and crosslinking reaction: Weigh 100g of the acylated saponin seed embryo prepared in step S1 and place it in a four-necked flask containing 500mL of water. Stir to form a homogeneous suspension, adjust the pH to 4-5, raise the temperature of the reaction system to 50℃, and then add 3g of initiator solution. The initiator solution is a mixture of 1g of 30% hydrogen peroxide, 8mL of water, and 0.5g of acetylacetone. Simultaneously with the addition of the initiator, begin slowly and uniformly adding the grafting monomer solution, which includes 30g of 40% diacetone acrylamide aqueous solution and 15mL of glycidyl methacrylate solution. Control the addition process to be completed within 1 hour. After all monomers have been added, continue the reaction at 50℃ for 3 hours to obtain the grafted modified saponin seed embryo polymer. Add 4g of N,N-bisphenylaminotetrahydrofuran crosslinking agent solution and 5g of sodium dodecyl sulfate to the above grafted polymer system, raise the temperature of the reaction system to 80℃, and continue the reaction for 1 hour. After the reaction is complete, the product is cooled to obtain the hydrated polymer adsorbent modified with soapberry seed embryo.

[0055] Example 2 A method for preparing a hydrated polymeric adsorbent modified with soapberry seed embryos includes the following preparation steps: S10, Acylation modification of soapberry seed embryos: 200 g of 3% saponin seed embryo dispersion was added to a three-necked flask equipped with a mechanical stirrer, thermometer, and reflux condenser. The pH of the dispersion was adjusted to 9.0 with 1 mol / L sodium hydroxide solution, and the hydration reaction was carried out for 50 min. Under the condition of reaction temperature of 40℃ and continuous stirring, 40% maleic anhydride (based on the mass of saponin seed embryo) was slowly added dropwise. During the reaction, the pH of the system was maintained constant using 1 mol / L sodium hydroxide solution, and the reaction was continued for 90 min. After the reaction was completed, the reaction system was immediately placed in an ice-water bath to terminate the reaction. Then, the mixture was placed in a dialysis bag with a molecular weight cutoff of 7 kDa and dialyzed for 72 hours to completely remove unreacted maleic anhydride and by-product salt ions. Finally, the dialyzed product was freeze-dried to obtain loose and porous acylated saponin seed embryos.

[0056] S20, graft copolymerization and crosslinking reaction: Weigh 50g of the acylated saponin seed embryo prepared in step S10 and place it in a four-necked flask containing 500mL of water. Stir to form a homogeneous suspension, adjust the pH to 4-5, raise the temperature of the reaction system to 50℃, and then add 1g of initiator solution. The initiator solution is a mixture of 1g of 30% hydrogen peroxide, 8mL of water, and 0.5g of acetylacetone. Simultaneously with the addition of the initiator, begin slowly and uniformly adding the grafting monomer solution, which includes 30g of 40% diacetone acrylamide aqueous solution and 10mL of glycidyl methacrylate solution. Control the addition process to be completed within 1 hour. After all monomers have been added, continue the reaction at 50℃ for 3 hours to obtain the grafted modified saponin seed embryo polymer. Add 3g of N,N-bisphenylaminotetrahydrofuran crosslinking agent solution and 5g of sodium dodecyl sulfate to the above grafted polymer system, raise the temperature of the reaction system to 80℃, and continue the reaction for 1 hour. After the reaction is complete, the product is cooled to obtain the hydrated polymer adsorbent modified with soapberry seed embryo.

[0057] Example 3 A method for preparing a hydrated polymeric adsorbent modified with soapberry seed embryos includes the following preparation steps: S10, Acylation modification of soapberry seed embryos: 200 g of 3% saponin seed embryo dispersion was added to a three-necked flask equipped with a mechanical stirrer, thermometer, and reflux condenser. The pH of the dispersion was adjusted to 9.0 with 1 mol / L sodium hydroxide solution, and the hydration reaction was carried out for 50 min. Under the condition of reaction temperature of 40℃ and continuous stirring, 30% maleic anhydride (based on the mass of saponin seed embryo) was slowly added dropwise. During the reaction, the pH of the system was maintained constant using 1 mol / L sodium hydroxide solution, and the reaction was continued for 90 min. After the reaction was completed, the reaction system was immediately placed in an ice-water bath to terminate the reaction. Then, the mixture was placed in a dialysis bag with a molecular weight cutoff of 7 kDa and dialyzed for 72 hours to completely remove unreacted maleic anhydride and by-product salt ions. Finally, the dialyzed product was freeze-dried to obtain loose and porous acylated saponin seed embryos.

[0058] S20, graft copolymerization and crosslinking reaction: Weigh 100g of the acylated saponin seed embryo prepared in step S1 and place it in a four-necked flask containing 500mL of water. Stir to form a homogeneous suspension, adjust the pH to 4-5, raise the temperature of the reaction system to 50℃, and then add 2.5g of initiator solution. The initiator solution is a mixture of 1g of 30% hydrogen peroxide, 8mL of water, and 0.5g of acetylacetone. Simultaneously with the addition of the initiator, slowly and uniformly add the grafting monomer solution, which includes 30g of 40% diacetone acrylamide aqueous solution and 15mL of glycidyl methacrylate solution. Control the addition process to be completed within 1 hour. After all monomers have been added, continue the reaction at 50℃ for 3 hours to obtain the grafted modified saponin seed embryo polymer. Add 4g of N,N-bisphenylaminotetrahydrofuran crosslinking agent solution and 10g of sodium dodecyl sulfate to the above grafted polymer system, raise the temperature of the reaction system to 80℃, and continue the reaction for 1 hour. After the reaction is complete, the product is cooled to obtain the hydrated polymer adsorbent modified with soapberry seed embryo.

[0059] Example 4 A method for preparing a hydrated polymeric adsorbent modified with soapberry seed embryos includes the following preparation steps: S1. Acylation modification of soapberry seed embryos: 200 g of 3% saponin seed embryo dispersion was added to a three-necked flask equipped with a mechanical stirrer, thermometer, and reflux condenser. The pH of the dispersion was adjusted to 9.0 with 1 mol / L sodium hydroxide solution, and the hydration reaction was carried out for 50 min. Under the condition of reaction temperature of 40℃ and continuous stirring, 20% maleic anhydride (based on the mass of saponin seed embryo) was slowly added dropwise. During the reaction, the pH of the system was maintained constant using 1 mol / L sodium hydroxide solution, and the reaction was continued for 90 min. After the reaction was completed, the reaction system was immediately placed in an ice-water bath to terminate the reaction. Then, the mixture was placed in a dialysis bag with a molecular weight cutoff of 7 kDa and dialyzed for 72 hours to completely remove unreacted maleic anhydride and by-product salt ions. Finally, the dialyzed product was freeze-dried to obtain loose and porous acylated saponin seed embryos.

[0060] S2. Graft copolymerization and crosslinking reaction: Weigh 80g of the acylated saponin seed embryo prepared in step S1 and place it in a four-necked flask containing 500mL of water. Stir to form a homogeneous suspension, adjust the pH to 4-5, raise the temperature of the reaction system to 50℃, and then add 3g of initiator solution. The initiator solution is a mixture of 1g of 30% hydrogen peroxide, 8mL of water, and 0.5g of acetylacetone. Simultaneously with the addition of the initiator, slowly and uniformly add the grafting monomer solution, which includes 30g of 40% diacetone acrylamide aqueous solution and 10mL of glycidyl methacrylate solution. Control the addition process to be completed within 1 hour. After all monomers have been added, continue the reaction at 50℃ for 3 hours to obtain the grafted modified saponin seed embryo polymer. Add 3g of N,N-bisphenylaminotetrahydrofuran crosslinking agent solution and 8g of sodium dodecyl sulfate to the above grafted polymer system, raise the temperature of the reaction system to 80℃, and continue the reaction for 1 hour. After the reaction is complete, the product is cooled to obtain the hydrated polymer adsorbent modified with soapberry seed embryo.

[0061] Performance testing: The experiment used tertiary produced water (oil content 273 mg / L) from the "Bohai Century" FPSO in the Qinhuangdao 32-6 oilfield as the research object. A 10L sample was taken and preheated in a 60℃ constant-temperature water bath for 30 minutes as the test water sample. In actual production at this oilfield, the wellhead fluid is distributed via manifolds to two series of production separators (Tr1 and Tr2) for oil-water separation. The separated oil phase is pumped out, while the water phase is further processed in two series of hydrocyclones and finally discharged through a degassing tank. A self-made hydrated polymer adsorbent injection point is located before the production separator. During the experiment, the preheated water sample was quantitatively dispensed into multiple test bottles, and a certain amount of the self-made hydrated polymer adsorbent was added to each. After sealing, the bottles were rapidly stirred for 1 minute to ensure thorough mixing. The test bottles were then placed in constant-temperature water baths at different temperatures, and the time was recorded and the oil-water separation status was observed. After standing for a certain period, a water sample was taken from the middle section of the bottle to determine its oil content.

[0062] ① Equal volumes (100 mL) of test water samples were placed in a series of conical flasks. Under a constant temperature water bath at 60℃, self-made hydrated polymeric adsorbent and a market comparison sample (Tianjin Kewei water cleaner) were added at gradient concentrations (10, 20, 30, 40, 50, 60 mg / L) ranging from 10 to 60 mg / L. After sealing the conical flasks, the samples were rapidly stirred (or vortexed) for 1 minute to ensure thorough mixing. The samples were then returned to the water bath and allowed to settle for 10 minutes. Finally, the residual oil content of the water samples was measured to evaluate the oil removal effect. Results are shown below. Figure 2 .

[0063] Depend on Figure 2It can be seen that both the self-made example samples and the market comparison sample (Tianjin Kewei water cleaner) have oil removal and flocculation effects on oilfield produced water. Within a certain dosage range, as the dosage increases, the oil content of the oilfield produced water shows a trend of first rapidly decreasing and then gradually stabilizing. However, the performance of all self-made example samples is better than that of the market comparison sample (Tianjin Kewei water cleaner), proving the advanced nature and effectiveness of its formulation or process. Among them, Example 3 shows the best application potential and economic benefits. At a dosage of 40 mg / L, the oil content of the oilfield produced water is reduced to a minimum of 21 mg / L, and the oil removal rate of the self-made example sample reaches 92.3%, which is the strongest oil removal capacity. This may be because the molecular structure of the self-made example sample contains multiple functional groups, attributed to the directional adsorption of its amphiphilic molecular structure on the surface of emulsified oil droplets. This adsorption behavior can rapidly reduce the Zeta potential of oil droplets, destroying their interfacial stability through electrostatic neutralization. The attenuation of the interfacial film strength promotes the aggregation between oil droplets, allowing the dispersed emulsified microparticles to rapidly aggregate, coarsen, and float, thereby completing oil-water separation. Subsequently, the oil content in the produced water from the oilfield almost stopped decreasing. Therefore, in practical applications, the self-made polymer adsorbent can achieve the best results while reducing the cost of reagents for customers. The optimal dosage for produced water from the oilfield (oil content 273 mg / L) is 40 mg / L.

[0064] ② A series of water samples of equal volume (100 mL) were taken, with a reagent dosage of 40 mg / L. These samples were subjected to isothermal sedimentation in water baths at different temperatures (45, 50, 55, 60, 65, 70 °C). All samples were sealed and rapidly stirred for 1 minute to ensure thorough mixing, followed by 10 minutes of settling. The effect of temperature was assessed by measuring the oil content. Results are shown below. Figure 3 .

[0065] Depend on Figure 3 It is evident that, under a fixed dosage, temperature is the key factor affecting oil removal efficiency. The oil removal efficiency of all samples significantly increased with increasing temperature, exhibiting the following pattern: in the low and medium temperature range of 40℃ to 60℃, the oil content decreased rapidly with increasing temperature; however, when the temperature exceeded 60℃, the decreasing trend slowed significantly, and the oil removal efficiency gradually stabilized. Nevertheless, the performance of all self-made sample examples at different temperatures consistently outperformed the market comparison sample (Tianjin Kewei water cleaner), fully verifying the universal efficacy advantage of its formulation under different operating conditions. This is because increased temperature allows the self-made sample examples to diffuse and adsorb to the oil droplet interface more quickly. Simultaneously, the decrease in system viscosity and the enhancement of Brownian motion significantly increased the probability of oil droplet aggregation, thereby strengthening the flocculent's trapping and sweeping effect. However, it should be noted that the energy consumption cost associated with excessively high temperatures limits its economic viability. Therefore, in practical applications, the optimal reaction temperature for the self-made polymer adsorbent in oilfield produced water is 60℃.

[0066] In summary, the experimental results of the self-made polymer adsorbent in oilfield produced water are as follows: with a dosage of 40 mg / L, a reaction time of 10 min, and a reaction temperature of 60℃, the oil content in the wastewater can be reduced to 21.3 mg / L, and the oil removal rate can reach 92.2%.

[0067] (II) To evaluate the removal performance of the self-made polymeric adsorbent for heavy metal ions, single-factor adsorption experiments were conducted in this study. First, a precise amount of the self-made polymeric adsorbent was weighed, and different concentrations of Pb were added. 2+ In solution, after adjusting the solution to the predetermined pH value, the reaction was shaken for 10 min at room temperature. After the reaction was completed, the supernatant was collected and the concentration of residual metal ions was determined using an atomic absorption spectrophotometer, and the removal rate E (%) was calculated accordingly.

[0068] Equation (1) In the formula: —Concentration of metal ions in the original solution, mg / L; —Concentration of metal ions in the adsorbate after adsorption, mg / L; ① Take a series of water samples of equal volume (100 mL), and set a series of pH gradients (3.0 to 8.0), with an initial concentration of 50 mg / L of Pb. 2+ 50 mg of a self-made polymeric adsorbent and a commercially available comparison sample (Futianbao heavy metal ion trapping and precipitating agent) were added to the solution, respectively. After shaking and reacting for 10 min at room temperature, the removal rate E of heavy metal ions was calculated to evaluate the effect of pH on the adsorption performance of the reagents. Results are shown below. Figure 4 .

[0069] Depend on Figure 4 It can be seen that the removal efficiency of the reagent for heavy metal ions exhibits a similar pattern with pH changes: within the acidic to neutral pH range, the removal rate increases significantly with increasing pH; after the pH reaches a certain critical value, the increase in removal rate tends to level off or reach a peak, and remains at a high level under neutral to weakly alkaline conditions; meanwhile, the adsorption effect of the self-made polymeric adsorbent on metal ions is generally superior to the market comparison sample (Futianbao heavy metal ion capturing and precipitating agent), with an adsorption rate of over 90%. This is because the self-made polymeric adsorbent has a huge specific surface area and abundant pores, and introduces a variety of active functional groups such as amide, carboxyl, and epoxy groups, which can efficiently capture heavy metal ions through multiple mechanisms such as coordination, ion exchange, and hydrogen bonding; under low pH conditions, high concentrations of H+... + With Pb 2+Competition for adsorption sites leads to protonation of the reagent molecules, resulting in a positive charge and electrostatic repulsion with the target metal ions, thus inhibiting adsorption. As pH increases, the reagent molecules gradually deprotonate and exist in anionic form, enhancing the electrostatic attraction and coordination with the metal cations, thereby increasing the adsorption capacity. However, when the pH is too high (7-8), the concentration of OH- in the solution increases, and metal ions easily form hydroxide precipitates, which compete with adsorption. In summary, the optimal pH for the self-made polymeric adsorbent to Pb²⁺ is 6.0.

[0070] ② Take a series of equal volumes (100 mL) of water samples, set the pH value to 6.0, and add reagents of varying mass gradients (20, 30, 40, 50, 60, 70 mg) to an initial concentration of 50 mg / L Pb²⁺ solution. After shaking and reacting all samples at room temperature for 10 minutes, calculate the removal rate R of heavy metal ions to evaluate the effect of dosage on reagent adsorption performance. Results are shown below. Figure 5 .

[0071] Figure 5 It can be seen that with the increase of the dosage, the removal rate of Pb2+ shows a rapid increase followed by a gradual plateau. When the dosage reaches 50 mg, the removal rate exceeds 90%, indicating that the adsorption process is close to saturation. Meanwhile, the adsorption performance of all self-made sample examples at different dosages is consistently superior to the market comparison sample (Futianbao heavy metal ion trapping and precipitating agent), proving that its functional group design can provide more effective adsorption sites, resulting in higher adsorption efficiency and better economy. This is because the amide and carboxyl functional groups abundant on the molecular chain of the self-made polymer adsorbent can efficiently capture and remove lead (Pb2+) from water through coordination. 2+ Heavy metal ions. However, when the dosage exceeded 50 mg, the removal rate decreased slightly. This may be because excessive reagent molecules collided and aggregated in the solution due to their own charges, causing some active adsorption sites to be shielded or encapsulated, resulting in a decrease in effective utilization. Therefore, considering both adsorption efficiency and economic cost, 50 mg was determined to be the optimal dosage.

[0072] ③ Take a series of water samples of equal volume (100 mL) and set initial Pb concentrations at gradients (10 mg / L, 50 mg / L, 100 mg / L, 150 mg / L, 200 mg / L, 250 mg / L). 2+ The solution was adjusted to pH 6, and then 50 mg of the reagent was added to each solution. The mixture was shaken at room temperature for 10 min, and the removal rate R was calculated. The removal of Pb was investigated. 2+ Initial concentration of solution for Pb 2+ The effect of adsorption performance, the results are as follows Figure 6 As shown.

[0073] Depend onFigure 6 It can be seen that Pb 2+ The initial concentration of Pb significantly affects the performance of the adsorbent; its removal rate gradually decreases with increasing initial concentration. However, all self-made polymeric adsorbents exhibited superior performance compared to commercially available samples. This phenomenon may be due to the fact that a certain amount of self-made polymeric adsorbent reacts with Pb... 2+ The effective active adsorption sites for binding are also limited. Under low concentration conditions, Pb 2+ It can fully contact and bind to the active sites, resulting in strong mass transfer driving force and thus a high removal rate. When Pb in the solution... 2+ When Pb reaches a certain binding amount with the active adsorption sites of the drug, 2+ As the concentration of Pb continues to increase, the amount of unadsorbed Pb in the solution... 2+ The quantity will also increase, leading to a decrease in the adsorption effect of the reagent. Therefore, the adsorption reaction of Pb by the self-made polymer adsorbent... 2+ The optimal initial concentration is 50 mg / L.

[0074] In summary, the experimental results of the self-made polymer adsorbent in heavy metal ion wastewater are as follows: with an initial heavy metal ion concentration of 50 mg / L, pH=6, and a dosage of 50 mg of the self-made polymer adsorbent, the removal rate of Pb2+ can reach over 90%.

[0075] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A hydrated polymeric adsorbent, characterized in that, It is a three-dimensional network structure material formed by modifying soapberry seed embryos by maleic anhydride acylation, then grafting and copolymerizing it with diacetone acrylamide and glycidyl methacrylate, and then crosslinking it with N,N-bisphenyltetrahydrofuran; the adsorbent molecular chain is rich in amide groups, carboxyl groups and epoxy functional groups.

2. A method for preparing the hydrated polymeric adsorbent as described in claim 1, characterized in that, Includes the following steps: S10. Acylation modification of soapberry seed embryos: The soapberry seed embryo dispersion was adjusted to alkaline pH, and maleic anhydride of 10%-40% of the soapberry seed embryo mass was added at 40℃±5℃ to carry out the reaction. The pH value of the system was kept constant during the reaction. After the reaction was completed, the acylated soapberry seed embryos were obtained by dialysis and freeze drying. S20. Graft copolymerization and crosslinking reaction: The acylated saponin seed embryos obtained in step S10 are dispersed in water, the pH is adjusted to 4-5, the temperature is raised to 50℃±5℃, an initiator solution composed of hydrogen peroxide and acetylacetone is added, and a mixed monomer of diacetone acrylamide aqueous solution and glycidyl methacrylate is added dropwise to carry out a graft copolymerization reaction. After the reaction is completed, N,N-bisphenylaminotetrahydrofuran crosslinking agent and sodium dodecyl sulfate are added, and the temperature is raised to 80℃±5℃ to carry out a crosslinking reaction to obtain the hydrated polymer adsorbent.

3. The method as described in claim 2, characterized in that, In step S10, the mass concentration of the soapberry seed embryo dispersion is 3%, which is prepared by stirring 3g of soapberry seed embryo powder with 197g of water at a constant speed for 10 minutes.

4. The method as described in claim 2, characterized in that, In step S10, the pH of the dispersion is adjusted to 9.0 using a 1 mol / L sodium hydroxide solution, and the acylation reaction is carried out while maintaining this pH value for 90 minutes.

5. The method as described in claim 2, characterized in that, In step S20, the initiator solution contains a 30% aqueous solution of hydrogen peroxide, with a mass ratio of 2:1 to acetylacetone.

6. The method as described in claim 2, characterized in that, In step S20, the diacetone acrylamide is added in the form of a 40% aqueous solution, and the mass ratio of diacetone acrylamide to glycidyl methacrylate is between 0.7:1 and 1.2:

1.

7. The method as described in claim 2, characterized in that, In step S20, the total mass ratio of the acylated saponin seed embryo to the mixed monomers is between 1:0.28 and 1:0.

65.

8. The method as described in claim 2, characterized in that, In step S20, the graft copolymerization reaction is carried out at 50°C for 3 hours, and the crosslinking reaction is carried out at 80°C for 1 hour.

9. The application of the hydrated polymer adsorbent as described in claim 1 in the treatment of oily wastewater or emulsified oil.

10. The application of the hydrated polymer adsorbent as described in claim 1 in the adsorption and removal of heavy metal ions in water, characterized in that, The heavy metal ions include Pb. 2+ Cu 2+ or Cd 2+ .

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