A porous adsorptive filter element material and a method of making the same

Abstract

The present application relates to the field of porous adsorption filter material, and particularly to a porous adsorption filter material and a preparation method thereof, which are used to solve the problems of insufficient heavy metal purification capacity, poor erosion resistance and short service life of the existing polypropylene water purification filter core; the polypropylene powder, maleic anhydride grafted polypropylene are added into a high-speed mixer, the antibacterial agent, the antioxidant 1010, the antioxidant 168, the composite inorganic filler, the activated composite pore-forming agent mixture and the dicumyl peroxide are added respectively, and then stirred to obtain a mixed powder; then the mixed powder is loaded into a mold for cold pressing forming, and then the filter core matrix is prepared through temperature control and solidification; then the filter core matrix is treated by a plasma machine; the organic-inorganic hybrid emulsion and the water-based epoxy curing agent are mixed and then sprayed on the outer cylindrical surface of the filter core; then the sprayed filter core is dried and solidified, cooled, washed and vacuum dried to obtain the porous adsorption filter material; the porous adsorption filter material has excellent heavy metal purification capacity, is resistant to water flow erosion, has high mechanical strength and a longer service life.

Description

Technical Field

[0001] This invention relates to the field of porous adsorption filter materials, and specifically to a porous adsorption filter material and its preparation method. Background Technology

[0002] During the drinking water purification process, harmful substances such as heavy metal ions and residual chlorine can endanger human health. Polypropylene porous filter cartridges are widely used in the field of household water purification due to their simple molding and excellent water permeability.

[0003] Currently, conventional polypropylene filter cartridges rely solely on the pores of the matrix itself for simple physical interception, lacking targeted purification components. They are extremely ineffective at removing heavy metal ions such as lead and cadmium from water, making it difficult to meet the needs of deep water purification. Some filter cartridges on the market directly mix in unmodified activated carbon and clay-based fillers, relying solely on physical adsorption to treat pollutants. This results in weak adsorption selectivity, limited adsorption capacity, and the easy desorption and precipitation of pollutants after long-term water flow, leading to insufficient water purification stability.

[0004] Meanwhile, ordinary polypropylene filter cartridges lack a protective structure on their surface, and the bonding strength of the matrix filler is relatively low. Long-term continuous scouring by water flow can easily lead to powder shedding and structural damage, which not only shortens the service life of the filter cartridge but also causes secondary pollution of the effluent water. Furthermore, the overall mechanical strength of the filter cartridge is relatively weak, and it is prone to deformation and damage under pressure, resulting in a short actual service life. It is impossible to balance high water purification efficiency with long-term performance. Therefore, it is urgent to optimize the formula and preparation process and develop porous adsorption filter cartridge materials that combine excellent heavy metal removal capabilities, scouring resistance, and mechanical stability. Summary of the Invention

[0005] In order to overcome the above-mentioned technical problems, the purpose of this invention is to provide a porous adsorption filter material and its preparation method.

[0006] The objective of this invention can be achieved through the following technical solutions: In a first aspect, this application provides a porous adsorption filter material, including a filter substrate and an organic-inorganic hybrid coating attached to the surface of the filter substrate; The filter element substrate is prepared from the following components in parts by weight: 4,4'-Oxobis(benzenesulfonyl)hydrazine 4.2-4.8 parts, sodium bicarbonate 0.8-1.0 parts, active zinc oxide 0.06-0.18 parts, polypropylene powder 43-48 parts, maleic anhydride-grafted polypropylene 7.5-9.0 parts, antibacterial agent 0.6-0.7 parts, antioxidant 1010 0.12-0.18 parts, antioxidant 168 0.12-0.18 parts, composite inorganic filler 4.5-6.5 parts, and dicumyl peroxide 0.6-0.8 parts; The organic-inorganic hybrid coating is prepared from the following components in parts by weight: 60-70 parts organic-inorganic hybrid emulsion, 7-8 parts water-based epoxy curing agent; The organic-inorganic hybrid emulsion is prepared by the following steps: Step a1: Add 4-methylhexahydrophthalic anhydride and 1,6-hexanediol to a four-necked flask equipped with a stirrer, thermometer, gas delivery tube, water separator and spherical condenser. Purge with nitrogen for protection and stir the reaction at 140-150℃ and 230-250 r / min for 4-5 h. Then cool naturally to room temperature to obtain bis(2-carboxy-4-methylcyclohexylformoxy)hexane. Step a2: Add bis(2-carboxy-4-methylcyclohexylformoxy)hexane, liquid epoxy resin, and tetraethylammonium bromide to a four-necked flask equipped with a stirrer, thermometer, gas delivery tube, and spherical condenser. Purge with nitrogen for protection and stir the reaction at 115-120℃ and a stirring speed of 280-300 r / min for 2.5-3.0 h. Allow the mixture to cool naturally to 90℃, add propylene glycol methyl ether, stir for 30-32 min, cool to 68℃, and increase the stirring speed to 48 rpm. Add the compound emulsifier at 0-500 r / min and stir for 25-30 min. Then increase the stirring speed to 2000-2200 r / min and add 68℃ deionized water dropwise through a constant pressure dropping funnel. The first 1 / 3 of the water is added at a rate of 1 mL / min, and then the rate is increased to 3 mL / min. Add the remaining deionized water. After the addition is complete, continue stirring for 30-35 min and allow it to cool naturally to room temperature. Filter the solution through a 200-mesh nylon filter to obtain the modified waterborne epoxy resin emulsion. Step a3: Add deionized water to a beaker, adjust the pH to 4.5 by adding acetic acid dropwise, and add γ-glycidoxypropyltrimethoxysilane while stirring at a speed of 200-220 rpm. Continue stirring for 20-25 minutes, then distill under reduced pressure for 15 minutes at 40°C and -0.08 MPa. Afterward, adjust the pH of the silica sol separately to 4.5-5.0 with acetic acid before adding it dropwise to the beaker. Then place the beaker in an ultrasonic cleaner and turn on the power. Pulsed ultrasound mode (5s on / 2s off), power 200-250W, ultrasound for 40-45 minutes under ice bath conditions (1 minute off every 10 minutes of ultrasound). After ultrasound, adjust the stirring rate to 280-300 r / min, pour the modified waterborne epoxy resin emulsion into the beaker, stir for 15-17 minutes, then adjust the pH to 8.8 with ammonia, add distilled water while stirring, dilute to a solid content of 32%, filter through a 400-mesh nylon filter to obtain an organic-inorganic hybrid emulsion.

[0007] In a preferred embodiment of the present invention, the ratio of 4-methylhexahydrophthalic anhydride to 1,6-hexanediol in step a1 is 2-2.4 mol: 1-1.2 mol.

[0008] In a preferred embodiment of the present invention, the ratio of bis(2-carboxy-4-methylcyclohexylformoxy)hexane, liquid epoxy resin, tetraethylammonium bromide, propylene glycol methyl ether, compound emulsifier and deionized water in step a2 is 1-1.2 mol: 2.05-2.46 mol: 6-7.2 g: 38-45.6 g: 90-108 g: 230-280 g.

[0009] In a preferred embodiment of the present invention, the liquid epoxy resin in step a2 is of type NPEL-128.

[0010] In a preferred embodiment of the present invention, the compound emulsifier in step a2 is a mixture of emulsifier AEO-9 and Span 60 in a ratio of 3g:1g.

[0011] In a preferred embodiment of the present invention, the ratio of deionized water, γ-glycidyl etheroxypropyltrimethoxysilane, silica sol and modified waterborne epoxy resin emulsion in step a3 is 20-22 mL: 0.8-0.9 g: 5.3-5.9 g: 80-90 g.

[0012] In a preferred embodiment of the present invention, the silica sol in step a3 is of type HS-830.

[0013] The composite inorganic filler is prepared by the following steps: Step b1: Add coconut shell activated carbon, diatomaceous earth, and attapulgite to a beaker and stir for 10-12 minutes at a stirring rate of 280-300 r / min. Then add hydrochloric acid solution and stir for 2-2.2 hours at a temperature of 65-70℃ and a stirring rate of 330-350 r / min. Filter the mixture and wash the filter cake with deionized water until the pH is neutral. Then place it in a vacuum drying oven and dry it at a temperature of 78-80℃ for 6-6.2 hours. Allow it to cool naturally to room temperature and grind it through a 120-mesh sieve to obtain the acid-washed inorganic filler. Step b2: Adjust the pH of the hydroxyethylidene diphosphonic acid aqueous solution to 4 with citric acid, then add the acid-washed inorganic filler, and ultrasonically impregnate for 30-32 minutes at a temperature of 48-50℃, an ultrasonic power of 200W, and an auxiliary stirring rate of 280r / min. Filter the mixture, wash the filter cake 3 times with sodium chloride solution, and then wash it 6-8 times with deionized water. Place it in a vacuum drying oven and dry it at a temperature of 68-70℃ for 4-4.2 hours. Allow it to cool naturally to room temperature, grind it through a 120-mesh sieve, and obtain the composite inorganic filler.

[0014] In a preferred embodiment of the present invention, the ratio of coconut shell activated carbon, diatomaceous earth, attapulgite, and hydrochloric acid solution in step b1 is 42-44g: 9.6-10g: 6-6.3g: 600-800mL.

[0015] In a preferred embodiment of the present invention, the molar concentration of the hydrochloric acid solution in step b1 is 4 mol / L.

[0016] In a preferred embodiment of the present invention, the ratio of the aqueous solution of hydroxyethylidene diphosphonic acid and the acid-washed inorganic filler in step b2 is 90-96g: 30-32g.

[0017] In a preferred embodiment of the present invention, the molar concentration of the sodium chloride solution in step b2 is 0.2 mol / L; and the mass fraction of the hydroxyethylidene diphosphonic acid aqueous solution is 3%.

[0018] Secondly, this application provides a method for preparing a porous adsorption filter material, comprising the following steps: Step 1: Weigh the following components by weight for the filter element matrix: 4,4'-oxobisbenzenesulfonyl hydrazine 4.2-4.8 parts, sodium bicarbonate 0.8-1.0 parts, active zinc oxide 0.06-0.18 parts, polypropylene powder 43-48 parts, maleic anhydride-grafted polypropylene 7.5-9.0 parts, antibacterial agent 0.6-0.7 parts, antioxidant 1010 0.12-0.18 parts, antioxidant 168 0.12-0.18 parts, composite inorganic filler 4.5-6.5 parts, and dicumyl peroxide 0.6-0.8 parts; Weigh the following components by weight for the coating: organic-inorganic hybrid emulsion 60-70 parts, water-based epoxy curing agent 7-8 parts, for later use; Step 2: Place 4,4'-oxobisbenzenesulfonyl hydrazine, sodium bicarbonate and active zinc oxide into an agate mortar, grind and mix for 15-17 minutes, and pass through a 200-mesh sieve to obtain an activated composite pore-forming agent mixture. Step 3: Place the polypropylene powder and maleic anhydride-grafted polypropylene in a vacuum drying oven and dry them at 78-80℃ for 4-4.2 hours. Then, add them to a high-speed mixer, add an antibacterial agent, and stir for 2-3 minutes at a stirring speed of 280-300 r / min. Then, add antioxidant 1010 and antioxidant 168, and continue stirring for 3-4 minutes. Add the mixture of composite inorganic filler and activated composite pore-forming agent, and stir at a high speed of 480-500 r / min for 10-12 minutes. Add dicumyl peroxide, reduce the speed to 180-200 r / min, and stir for 2-3 minutes to obtain the mixed powder. Step 4: Fill the mold with the mixed powder while gently shaking to remove air. Then place the mold in a hydraulic cold pressing molding equipment, set the molding pressure to 3MPa, hold the pressure at room temperature for 5-6 minutes, release the pressure and demold. Then place it vertically in a programmable temperature-controlled electric curing kiln, introduce high-purity nitrogen to replace the air in the kiln, and maintain a nitrogen protective atmosphere throughout the process. Increase the temperature from room temperature to 120℃ at a heating rate of 5℃ / min, hold for 20 minutes, then increase the temperature to 155℃ at a heating rate of 2℃ / min, hold for 30 minutes, then increase the temperature to 162℃ at a heating rate of 3℃ / min, hold for 8 minutes, and then control the kiln cooling rate to ≤1℃ / min to cool to room temperature to obtain the filter element substrate. Step 5: Treat the filter element substrate with an atmospheric pressure air plasma machine (600-800W). Keep the spray gun 7cm away from the filter element surface and rotate the filter element at a constant speed of 15r / min. Sweep the front and back sides twice each. Use low-pressure air spraying with a 1mm nozzle diameter and an atomization pressure of 0.2MPa. Take an organic-inorganic hybrid emulsion and add a water-based epoxy curing agent while stirring at 280-300r / min. Stir for 10-12 minutes and then spray the mixture onto the outer cylindrical surface of the filter element in two coats. Allow each coat to air dry at room temperature for 8-9 minutes after application. Spray the next coat, and after spraying, place it in a program-controlled temperature hot air oven. Heat at a rate of 0.8℃ / min, first dry at 70℃ for 90 minutes, then heat to 100℃ and hold for 30 minutes, then heat to 110℃ and hold for 75 minutes. Let it cool naturally in the oven to below 40℃ and take it out. Then rinse the entire filter element with 60℃ deionized water in a reverse flow for 15-17 minutes. After that, place it in a vacuum drying oven and dry at 55-60℃ for 90-100 minutes to obtain the porous adsorption filter element material.

[0019] In a preferred embodiment of the present invention, the polypropylene powder is of type PPH045; the maleic anhydride-grafted polypropylene is of type CMG9801; the waterborne epoxy curing agent is of type AB-HGA-70; and the antibacterial agent is of type RS-CZY.

[0020] The beneficial effects of this invention are: This invention discloses a porous adsorption filter material and its preparation method. The method involves grinding and mixing 4,4'-oxobisbenzenesulfonyl hydrazine, sodium bicarbonate, and activated zinc oxide, then sieving to obtain an activated composite pore-forming agent mixture. Polypropylene powder and maleic anhydride-grafted polypropylene are added to a high-speed mixer, along with an antibacterial agent, antioxidant 1010, antioxidant 168, composite inorganic filler, the activated composite pore-forming agent mixture, and dicumyl peroxide. The mixture is stirred to obtain a mixed powder. This mixed powder is filled into a filter mold, pressurized, demolded, and the green body is vertically placed in an electric curing kiln for sintering to obtain a filter substrate. The filter substrate is treated with a plasma machine. An organic-inorganic hybrid emulsion and a water-based epoxy curing agent are mixed to obtain a spraying liquid, which is sprayed onto the outer cylindrical surface of the filter. After spraying, the filter is placed in a hot air oven for drying, cooling, rinsing, and vacuum drying to obtain the final product. This porous adsorption filter material utilizes a gradient temperature-controlled foaming process to create a uniformly interconnected three-dimensional porous structure. It combines high water flow rate with ample adsorption contact area. The uniformly dispersed modified composite inorganic filler within simultaneously achieves physical adsorption and highly selective chelation of heavy metal ions, efficiently removing heavy metals such as lead, cadmium, and copper, as well as residual chlorine and organic matter from water. The organic-inorganic hybrid coating on the surface is firmly bonded to the polypropylene matrix, significantly improving the filter's resistance to water flow and mechanical stability. This protects the internal porous structure from water flow damage, extending its service life. Furthermore, the material exhibits excellent overall mechanical strength, resisting deformation and breakage, and meeting drinking water safety standards. This results in a porous adsorption filter material with superior heavy metal purification capabilities, high water flow resistance, high mechanical strength, and a longer service life.

[0021] In the preparation of porous adsorption filter material, an organic-inorganic hybrid emulsion was first prepared. Firstly, 4-methylhexahydrophthalic anhydride and 1,6-hexanediol underwent an anhydride alcoholysis ring-opening reaction to generate bis(2-carboxy-4-methylcyclohexylformyloxy)hexane. After ring-opening, the anhydride reacted with the glycol hydroxyl groups, retaining free carboxyl groups, which provided active sites for subsequent ring-opening reactions with epoxy resin. The alicyclic structure of 4-methylhexahydrophthalic anhydride endowed the product with high rigidity and thermal stability, while the long chain of 1,6-hexanediol provided flexibility, balancing the brittleness of the coating. Subsequently, the dicarboxylic acid ester intermediate reacted with liquid epoxy resin in a tetrahydrocarbonyl ester reaction. Under the catalysis of ethylammonium bromide, a ring-opening reaction occurs, in which the two carboxyl groups of the intermediate attack the three-membered ring of the epoxy group, causing it to break and forming ester bonds one-to-one, generating secondary hydroxyl groups to construct a branched modified epoxy resin structure. Subsequently, reverse emulsification is performed, dispersing the compounded emulsifier in the low-viscosity resin. Deionized water is added dropwise, initially slowly and then rapidly, changing the system from water-in-oil to oil-in-water. The resin is dispersed into stable colloidal particles, ultimately yielding a modified waterborne epoxy resin emulsion. First, γ-glycidoxypropyltrimethoxysilane is hydrolyzed under acidic conditions, converting the methoxy group in the molecule into a silanol group and releasing methanol. After vacuum distillation, the silane hydrolysate reacts with silica sol. The silanol groups of the hydrolysate undergo dehydration condensation with the silanol groups on the silica sol surface, forming stable Si-O-Si covalent bonds. This allows the silane with epoxy groups to be grafted onto the surface of nano-silica particles. Then, it is mixed with a modified epoxy resin emulsion. The epoxy groups of the silane can form hydrogen bonds with the hydroxyl and carboxyl groups in the resin and participate in the cross-linking reaction during subsequent curing, ultimately forming an organic-inorganic hybrid emulsion. The organic-inorganic hybrid emulsion exhibits extremely strong adhesion to the polypropylene matrix. After plasma treatment, the polar groups such as hydroxyl and carbonyl groups on the polypropylene surface can adhere to the emulsion. The hydroxyl, carboxyl, and ether bonds in the coating form strong hydrogen bonds and van der Waals forces, and the coating has good toughness and deformation ability, which can adapt to the thermal expansion and contraction during the use of the filter element. It also has excellent water resistance and chemical resistance. The hydrophobicity and chemical stability of the inorganic silica phase itself, combined with the dense three-dimensional cross-linked network after curing, can effectively block the penetration of water molecules and chemical media, and can also significantly enhance mechanical strength and wear resistance. More importantly, it does not affect the core function of the filter element. It only forms a thin coating on the outer cylindrical surface of the filter element and will not block the internal porous structure. In addition, it has excellent storage stability and workability.

[0022] In the preparation of porous adsorption filter material, a composite inorganic filler was first prepared. First, coconut shell activated carbon, diatomaceous earth, and attapulgite were mixed evenly and then treated with high-temperature hydrochloric acid to increase the specific surface area and porosity, while exposing more surface hydroxyl sites. Then, the pH of the hydroxyethylidene diphosphonic acid solution was adjusted to weakly acidic using citric acid. Ultrasonic-assisted impregnation was then used to promote the diffusion of hydroxyethylidene diphosphonic acid molecules into the micropores of the filler, allowing phosphonic acid functional groups to bind to the surface of the acid-washed and activated inorganic filler through ionic and hydrogen bonds, introducing heavy metal chelating active sites. Finally, after washing, drying, and sieving, a composite inorganic filler with phosphonic acid groups loaded on its surface was obtained. This composite inorganic filler, composed of multiple adsorption substrates, exhibits significantly enhanced physical adsorption and pore retention capabilities after acid washing. The phosphonic acid groups loaded on the surface effectively target Pb in water. 2+ Cd 2+ The heavy metal ions exhibit highly selective chelation, resulting in excellent water purification. They also possess good chemical stability and resistance to water flow erosion. With the assistance of added maleic anhydride-grafted polypropylene, they have good compatibility with the polypropylene matrix, allowing them to be evenly dispersed inside the filter element without damaging the porous foam structure. This ensures both water and air permeability of the filter element and stable heavy metal purification. Furthermore, the preparation process is mild and leaves no toxic residues, meeting drinking water safety standards. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1: This embodiment describes a method for preparing a porous adsorption filter material, including the following steps: Step S1: 2 mol of 4-methylhexahydrophthalic anhydride and 1 mol of 1,6-hexanediol were added to a four-necked flask equipped with a stirrer, thermometer, gas delivery tube, water separator and spherical condenser. Nitrogen gas was introduced for protection, and the mixture was stirred at 140℃ and 230 r / min for 4 h. After that, it was naturally cooled to room temperature to obtain bis(2-carboxy-4-methylcyclohexylformoxy)hexane. Step S2: Add 1 mol of bis(2-carboxy-4-methylcyclohexylformoxy)hexane, 2.05 mol of liquid epoxy resin (model NPEL-128), and 6 g of tetraethylammonium bromide to a four-necked flask equipped with a stirrer, thermometer, gas delivery tube, and spherical condenser. Purge with nitrogen and stir at 115°C and 280 r / min for 2.5 h. Allow to cool naturally to 90°C, add 38 g of propylene glycol methyl ether, stir for 30 min, cool to 68°C, increase the stirring speed to 480 r / min, add 90 g of compound emulsifier (a mixture of emulsifier AEO-9 and Span 60 in a 3 g:1 g ratio), stir for 25 min, then increase the stirring speed to 2000 r / min and add 230 g of the mixture dropwise through a constant pressure dropping funnel. Add 68℃ deionized water, with the first 1 / 3 of the water volume added at a rate of 1 mL / min, then increase the rate to 3 mL / min, and add the remaining deionized water. After the addition is complete, continue stirring for 30 min, allow to cool naturally to room temperature, and filter through a 200-mesh nylon filter to obtain the modified waterborne epoxy resin emulsion. Step S3: Add 20 mL of deionized water to a beaker, adjust the pH to 4.5 by adding acetic acid dropwise, and while stirring at 200 r / min, add 0.8 g of γ-glycidoxypropyltrimethoxysilane. Continue stirring for 20 min, then distill under reduced pressure for 15 min at 40℃ and -0.08 MPa. Next, adjust the pH of 5.3 g of silica sol (HS-830) to 4.5 separately with acetic acid, and then add it dropwise to the beaker. Then, place it in an ultrasonic cleaner, turn on the pulse ultrasonic mode (5s on / 2s off), the power is 200W, and ultrasonicate for 40 minutes under ice bath conditions (1 minute off every 10 minutes of ultrasonication). After ultrasonication, adjust the stirring speed to 280r / min, pour 80g of modified waterborne epoxy resin emulsion into a beaker, stir for 15 minutes, then adjust the pH to 8.8 with ammonia water, add distilled water while stirring, dilute to a solid content of 32%, filter with a 400-mesh nylon filter to obtain an organic-inorganic hybrid emulsion; Step S4: Add 42g of coconut shell activated carbon, 9.6g of diatomaceous earth and 6g of attapulgite to a beaker and stir for 10min at a stirring rate of 280r / min. Then add 600mL of hydrochloric acid solution (molar concentration of hydrochloric acid solution is 4mol / L) and stir for 2h at a temperature of 65℃ and a stirring rate of 330r / min. Filter and wash the filter cake with deionized water until the pH is neutral. Then place it in a vacuum drying oven and dry at a temperature of 78℃ for 6h. Let it cool naturally to room temperature and grind it through a 120-mesh sieve to obtain the acid-washed inorganic filler. Step S5: Adjust the pH of 90g of hydroxyethylidene diphosphonic acid aqueous solution (the mass fraction of hydroxyethylidene diphosphonic acid aqueous solution is 3%) to 4 with citric acid, then add 30g of acid-washed inorganic filler, and ultrasonically impregnate for 30min at a temperature of 48℃, an ultrasonic power of 200W, and an auxiliary stirring rate of 280r / min. Filter the mixture, wash the filter cake 3 times with sodium chloride solution (the molar concentration of sodium chloride solution is 0.2mol / L), and then wash it 6 times with deionized water. Place the mixture in a vacuum drying oven and dry it at a temperature of 68℃ for 4h. Allow it to cool naturally to room temperature, grind it through a 120-mesh sieve to obtain the composite inorganic filler. Step S6: Weigh the following components by weight: 4,4'-oxobisbenzenesulfonyl hydrazine 4.2 parts, sodium bicarbonate 0.8 parts, active zinc oxide 0.06 parts, polypropylene powder 43 parts, maleic anhydride-grafted polypropylene 7.5 parts, antibacterial agent 0.6 parts, antioxidant 1010 0.12 parts, antioxidant 168 0.12 parts, composite inorganic filler 4.5 parts, and dicumyl peroxide 0.6 parts; Weigh the following components by weight: organic-inorganic hybrid emulsion 60 parts, water-based epoxy curing agent 7 parts, for later use; Step S7: Place 4,4'-oxobisbenzenesulfonylhydrazine, sodium bicarbonate and active zinc oxide into an agate mortar, grind and mix for 15 minutes, and pass through a 200-mesh sieve to obtain an activated composite pore-forming agent mixture. Step S8: Place polypropylene powder (polypropylene powder model is PPH045) and maleic anhydride grafted polypropylene (maleic anhydride grafted polypropylene model is CMG9801) in a vacuum drying oven and dry at 78℃ for 4 hours. Then add it to a high-speed mixer, add antibacterial agent (antibacterial agent model is RS-CZY), and stir at a stirring speed of 280r / min for 2 minutes. Then add antioxidant 1010 and antioxidant 168, and continue stirring for 3 minutes. Add the mixture of composite inorganic filler and activated composite pore-forming agent, and stir at a high speed of 480r / min for 10 minutes. Add dicumyl peroxide, reduce the speed to 180r / min, and stir for 2 minutes to obtain the mixed powder. Step S9: Fill the mixed powder into the 10-inch standard cylindrical filter element mold (outer diameter 65mm, inner diameter 28mm), gently vibrate to remove air while filling, then place the mold in a hydraulic cold pressing molding equipment, set the molding pressure to 3MPa, hold the pressure at room temperature for 5 minutes, release the pressure and demold, then place it vertically in a programmable temperature-controlled electric curing kiln, introduce high-purity nitrogen to replace the air in the kiln, maintain a nitrogen protective atmosphere throughout the process, raise the temperature from room temperature to 120℃ at a heating rate of 5℃ / min, hold for 20 minutes, then raise the temperature to 155℃ at a heating rate of 2℃ / min, hold for 30 minutes, then raise the temperature to 162℃ at a heating rate of 3℃ / min, hold for 8 minutes, then control the kiln cooling rate to ≤1℃ / min, cool down to room temperature, and obtain the filter element substrate; Step S10: Treat the filter element substrate with a normal pressure air plasma machine (600W). Keep the spray gun 7cm away from the filter element surface and rotate the filter element at a constant speed of 15r / min. Sweep both sides twice. Use low-pressure air spraying with a 1mm nozzle diameter and an atomization pressure of 0.2MPa. Take an organic-inorganic hybrid emulsion and add a water-based epoxy curing agent (AB-HGA-70) at a stirring rate of 280r / min. Stir for 10 minutes and then spray onto the outer cylindrical surface of the filter element in two coats. Allow each coat to dry at room temperature for 8 minutes after application. The next coat is sprayed, and the average thickness of the coating on the outer cylindrical surface is controlled to be 25μm after curing. After spraying, the coating is placed in a programmable temperature-controlled hot air oven and heated at a rate of 0.8℃ / min. The coating is first dried at 70℃ for 90min, then heated to 100℃ and held for 30min, then heated to 110℃ and held for 75min. The coating is then allowed to cool naturally to below 40℃ and removed. The filter element is then rinsed with 60℃ deionized water in a reverse flow for 15min. After that, it is placed in a vacuum drying oven and dried at 55℃ for 90min to obtain the porous adsorption filter element material.

[0025] Example 2: This embodiment describes a method for preparing a porous adsorption filter material, including the following steps: Step S1: 2.2 mol of 4-methylhexahydrophthalic anhydride and 1.1 mol of 1,6-hexanediol were added to a four-necked flask equipped with a stirrer, thermometer, gas delivery tube, water separator and spherical condenser. Nitrogen gas was introduced for protection, and the mixture was stirred at 145 °C and 240 r / min for 4.5 h. After that, it was naturally cooled to room temperature to obtain bis(2-carboxy-4-methylcyclohexylformoxy)hexane. Step S2: 1.1 mol of bis(2-carboxy-4-methylcyclohexylformoxy)hexane, 2.2 mol of liquid epoxy resin (model NPEL-128), and 6.6 g of tetraethylammonium bromide were added to a four-necked flask equipped with a stirrer, thermometer, gas delivery tube, and spherical condenser. Nitrogen gas was introduced for protection, and the mixture was stirred at 117°C and a stirring speed of 290 r / min for 2.7 h. The mixture was then allowed to cool naturally to 90°C. 42.1 g of propylene glycol methyl ether was added, and the mixture was stirred for 31 min. The temperature was then lowered to 68°C, and the stirring speed was increased to 490 r / min. 99 g of a compound emulsifier (a mixture of emulsifier AEO-9 and Span 60 in a ratio of 3 g:1 g) was added, and the mixture was stirred for 27 min. The stirring speed was then increased to 2100 r / min, and 255 g of the mixture was added dropwise through a constant-pressure dropping funnel. Add 68℃ deionized water, with the first 1 / 3 of the water volume added at a rate of 1 mL / min, then increase the rate to 3 mL / min, and add the remaining deionized water. After the addition is complete, continue stirring for 32 min, allow to cool naturally to room temperature, and filter through a 200-mesh nylon filter to obtain the modified waterborne epoxy resin emulsion. Step S3: Add 21 mL of deionized water to a beaker, adjust the pH to 4.5 by adding acetic acid dropwise, and while stirring at 210 r / min, add 0.85 g of γ-glycidoxypropyltrimethoxysilane. Continue stirring for 23 min, then distill under reduced pressure for 15 min at 40 °C and -0.08 MPa. Afterward, adjust the pH of 5.6 g of silica sol (HS-830) to 4.7 separately with acetic acid, and then add it dropwise to the beaker. Then, place it in an ultrasonic cleaner, turn on the pulse ultrasonic mode (5s on / 2s off), power 230W, ultrasonicate for 43 minutes under ice bath conditions (1 minute off every 10 minutes of ultrasonication). After ultrasonication, adjust the stirring speed to 290r / min, pour 85g of modified waterborne epoxy resin emulsion into a beaker, stir for 16 minutes, then adjust the pH to 8.8 with ammonia water, add distilled water while stirring, dilute to a solid content of 32%, filter with a 400-mesh nylon filter to obtain an organic-inorganic hybrid emulsion; Step S4: Add 43g of coconut shell activated carbon, 9.8g of diatomaceous earth and 6.1g of attapulgite to a beaker and stir for 11min at a stirring rate of 290r / min. Then add 700mL of hydrochloric acid solution (molar concentration of hydrochloric acid solution is 4mol / L) and stir for 2.1h at a temperature of 67℃ and a stirring rate of 340r / min. Filter and wash the filter cake with deionized water until the pH is neutral. Then place it in a vacuum drying oven and dry at a temperature of 79℃ for 6.1h. Allow it to cool naturally to room temperature and grind it through a 120-mesh sieve to obtain the acid-washed inorganic filler. Step S5: Adjust the pH of 93g of hydroxyethylidene diphosphonic acid aqueous solution (the mass fraction of hydroxyethylidene diphosphonic acid aqueous solution is 3%) to 4 with citric acid, then add 31g of acid-washed inorganic filler, and ultrasonically impregnate for 31min at a temperature of 49℃, an ultrasonic power of 200W, and an auxiliary stirring rate of 280r / min. Filter the mixture, wash the filter cake 3 times with sodium chloride solution (molar concentration of sodium chloride solution is 0.2mol / L), and then wash it 7 times with deionized water. Place it in a vacuum drying oven and dry it at a temperature of 69℃ for 4.1h. Allow it to cool naturally to room temperature, grind it through a 120-mesh sieve to obtain the composite inorganic filler. Step S6: Weigh the following components by weight: 4,4'-oxobisbenzenesulfonyl hydrazine 4.5 parts, sodium bicarbonate 0.9 parts, active zinc oxide 0.12 parts, polypropylene powder 45.5 parts, maleic anhydride-grafted polypropylene 8.2 parts, antibacterial agent 0.65 parts, antioxidant 1010 0.15 parts, antioxidant 168 0.5 parts, composite inorganic filler 5.5 parts, and dicumyl peroxide 0.7 parts; Weigh the following components by weight: organic-inorganic hybrid emulsion 65 parts, water-based epoxy curing agent 7.5 parts, for later use; Step S7: Place 4,4'-oxobisbenzenesulfonyl hydrazine, sodium bicarbonate and active zinc oxide into an agate mortar, grind and mix for 16 minutes, and pass through a 200-mesh sieve to obtain an activated composite pore-forming agent mixture. Step S8: Place polypropylene powder (polypropylene powder model is PPH045) and maleic anhydride grafted polypropylene (maleic anhydride grafted polypropylene model is CMG9801) in a vacuum drying oven and dry at 79℃ for 4.1h. Then add it to a high-speed mixer, add antibacterial agent (antibacterial agent model is RS-CZY), and stir at a stirring speed of 290r / min for 2.5min. Then add antioxidant 1010 and antioxidant 168, and continue stirring for 3.5min. Add the mixture of composite inorganic filler and activated composite pore-forming agent, and stir at a high speed of 490r / min for 11min. Add dicumyl peroxide, reduce the speed to 190r / min, and stir for 2.5min to obtain the mixed powder. Step S9: Fill the mixed powder into the 10-inch standard cylindrical filter element mold (outer diameter 65mm, inner diameter 28mm), gently vibrate to remove air while filling, then place the mold in a hydraulic cold pressing molding equipment, set the molding pressure to 3MPa, hold the pressure at room temperature for 5.5min, release the pressure and demold, then place it vertically in a programmable temperature-controlled electric curing kiln, introduce high-purity nitrogen to replace the air in the kiln, maintain a nitrogen protective atmosphere throughout, raise the temperature from room temperature to 120℃ at a heating rate of 5℃ / min, hold for 20min, then raise the temperature to 155℃ at a heating rate of 2℃ / min, hold for 30min, then raise the temperature to 162℃ at a heating rate of 3℃ / min, hold for 8min, then control the kiln cooling rate to ≤1℃ / min, cool to room temperature, and obtain the filter element substrate; Step S10: Treat the filter element substrate with a 700W atmospheric pressure air plasma sprayer. Keep the spray gun 7cm away from the filter element surface and rotate the filter element at a constant speed of 15r / min. Sweep both sides twice. Use low-pressure air spraying with a 1mm nozzle diameter and an atomization pressure of 0.2MPa. Take an organic-inorganic hybrid emulsion and add a water-based epoxy curing agent (AB-HGA-70) at a stirring rate of 290r / min. Stir for 11 minutes and then spray onto the outer cylindrical surface of the filter element in two coats. Allow each coat to dry at room temperature for 8.5 minutes. Then spray the next coat, controlling the average thickness of the coating on the outer cylindrical surface to be 27μm after curing. After spraying, place it in a programmable temperature-controlled hot air oven and heat it at a rate of 0.8℃ / min. First, dry it at a drying temperature of 70℃ for 90min, then heat it to 100℃ and hold it for 30min, then heat it to 110℃ and hold it for 75min. Let it cool naturally in the oven to below 40℃ and take it out. Then rinse the entire filter element with 60℃ deionized water in a reverse flow for 16min. After that, place it in a vacuum drying oven and dry it at a temperature of 57℃ for 95min to obtain the porous adsorption filter element material.

[0026] Example 3: This embodiment describes a method for preparing a porous adsorption filter material, including the following steps: Step S1: 2.4 mol of 4-methylhexahydrophthalic anhydride and 1.2 mol of 1,6-hexanediol were added to a four-necked flask equipped with a stirrer, thermometer, gas delivery tube, water separator and spherical condenser. Nitrogen gas was introduced for protection, and the mixture was stirred for 5 h at 150 °C and a stirring rate of 250 r / min. After that, it was naturally cooled to room temperature to obtain bis(2-carboxy-4-methylcyclohexylformoxy)hexane. Step S2: 1.2 mol of bis(2-carboxy-4-methylcyclohexylformoxy)hexane, 2.46 mol of liquid epoxy resin (model NPEL-128), and 7.2 g of tetraethylammonium bromide were added to a four-necked flask equipped with a stirrer, thermometer, gas delivery tube, and spherical condenser. Nitrogen gas was introduced for protection, and the mixture was stirred at 120°C and a stirring speed of 300 r / min for 3.0 h. The mixture was then allowed to cool naturally to 90°C. 45.6 g of propylene glycol methyl ether was added, and the mixture was stirred for 32 min. The temperature was then lowered to 68°C, and the stirring speed was increased to 500 r / min. 108 g of a compound emulsifier (a mixture of emulsifier AEO-9 and Span 60 in a ratio of 3 g:1 g) was added, and the mixture was stirred for 30 min. The stirring speed was then increased to 2200 r / min, and 280 g of the compound emulsifier was added dropwise through a constant pressure dropping funnel. Add 68℃ deionized water, with the first 1 / 3 of the water volume added at a rate of 1 mL / min, then increase the rate to 3 mL / min, and add the remaining deionized water. After the addition is complete, continue stirring for 35 min, allow to cool naturally to room temperature, and filter through a 200-mesh nylon filter to obtain the modified waterborne epoxy resin emulsion. Step S3: Add 22 mL of deionized water to a beaker, adjust the pH to 4.5 by adding acetic acid dropwise, and while stirring at 220 r / min, add 0.9 g of γ-glycidoxypropyltrimethoxysilane. Continue stirring for 25 min, then distill under reduced pressure for 15 min at 40 °C and -0.08 MPa. Next, adjust the pH of 5.9 g of silica sol (HS-830) to 5.0 separately with acetic acid, and then add it dropwise to the beaker. Then, place it in an ultrasonic cleaner, turn on the pulse ultrasonic mode (5s on / 2s off), the power is 250W, and ultrasonicate for 45 minutes under ice bath conditions (1 minute off every 10 minutes of ultrasonication). After ultrasonication, adjust the stirring speed to 300r / min, pour 90g of modified waterborne epoxy resin emulsion into a beaker, stir for 17 minutes, then adjust the pH to 8.8 with ammonia water, add distilled water while stirring, dilute to a solid content of 32%, filter with a 400-mesh nylon filter to obtain an organic-inorganic hybrid emulsion; Step S4: Add 44g of coconut shell activated carbon, 10g of diatomaceous earth and 6.3g of attapulgite to a beaker and stir for 12min at a stirring rate of 300r / min. Then add 800mL of hydrochloric acid solution (molar concentration of hydrochloric acid solution is 4mol / L) and stir for 2.2h at a temperature of 70℃ and a stirring rate of 350r / min. Filter the mixture and wash the filter cake with deionized water until the pH is neutral. Then place it in a vacuum drying oven and dry it at a temperature of 80℃ for 6.2h. Allow it to cool naturally to room temperature and grind it through a 120-mesh sieve to obtain the acid-washed inorganic filler. Step S5: Adjust the pH of 96g of hydroxyethylidene diphosphonic acid aqueous solution (the mass fraction of hydroxyethylidene diphosphonic acid aqueous solution is 3%) to 4 with citric acid, then add 32g of acid-washed inorganic filler, and ultrasonically impregnate for 32min at a temperature of 50℃, an ultrasonic power of 200W, and an auxiliary stirring rate of 280r / min. Filter the mixture, wash the filter cake 3 times with sodium chloride solution (molar concentration of sodium chloride solution is 0.2mol / L), and then wash it 8 times with deionized water. Place it in a vacuum drying oven and dry it at a temperature of 70℃ for 4.2h. Allow it to cool naturally to room temperature, grind it through a 120-mesh sieve to obtain the composite inorganic filler. Step S6: Weigh the following components by weight: 4,4'-oxobisbenzenesulfonyl hydrazine 4.8 parts, sodium bicarbonate 1.0 part, active zinc oxide 0.18 parts, polypropylene powder 48 parts, maleic anhydride-grafted polypropylene 9.0 parts, antibacterial agent 0.7 parts, antioxidant 1010 0.18 parts, antioxidant 168 0.18 parts, composite inorganic filler 6.5 parts, and dicumyl peroxide 0.8 parts; Weigh the following components by weight: organic-inorganic hybrid emulsion 70 parts, water-based epoxy curing agent 8 parts, for later use; Step S7: Place 4,4'-oxobisbenzenesulfonyl hydrazine, sodium bicarbonate and active zinc oxide into an agate mortar, grind and mix for 17 minutes, and pass through a 200-mesh sieve to obtain an activated composite pore-forming agent mixture. Step S8: Place polypropylene powder (polypropylene powder model is PPH045) and maleic anhydride grafted polypropylene (maleic anhydride grafted polypropylene model is CMG9801) in a vacuum drying oven and dry at 80℃ for 4.2h. Then add it to a high-speed mixer, add antibacterial agent (antibacterial agent model is RS-CZY), stir at a stirring speed of 300r / min for 3min, then add antioxidant 1010 and antioxidant 168, continue stirring for 4min, add the composite inorganic filler and activated composite pore-forming agent mixture, stir at a stirring speed of 500r / min for 12min, add dicumyl peroxide, reduce the speed to 200r / min, stir for 3min to obtain mixed powder; Step S9: Fill the mixed powder into the 10-inch standard cylindrical filter element mold (outer diameter 65mm, inner diameter 28mm), gently vibrate to remove air while filling, then place the mold in a hydraulic cold pressing molding equipment, set the molding pressure to 3MPa, hold the pressure at room temperature for 6 minutes, release the pressure and demold, then place it vertically in a programmable temperature-controlled electric curing kiln, introduce high-purity nitrogen to replace the air in the kiln, maintain a nitrogen protective atmosphere throughout the process, raise the temperature from room temperature to 120℃ at a heating rate of 5℃ / min, hold for 20 minutes, then raise the temperature to 155℃ at a heating rate of 2℃ / min, hold for 30 minutes, then raise the temperature to 162℃ at a heating rate of 3℃ / min, hold for 8 minutes, then control the kiln cooling rate to ≤1℃ / min, cool down to room temperature, and obtain the filter element substrate; Step S10: Treat the filter element substrate with an atmospheric pressure air plasma machine (power 800W), with the spray gun 7cm away from the filter element surface. Rotate the filter element at a uniform speed of 15r / min, sweeping twice on both sides. Use low-pressure air spraying with a nozzle diameter of 1mm and an atomization pressure of 0.2MPa. Take an organic-inorganic hybrid emulsion and add a water-based epoxy curing agent (model AB-HGA-70) at a stirring rate of 300r / min. Stir for 12 minutes and use for spraying. Spray on the outer cylindrical surface of the filter element in two coats. After each coat, allow it to dry at room temperature for 9 minutes before... Spray the next coat, controlling the average thickness of the coating on the outer cylindrical surface to be 30μm after curing. After spraying, place it in a programmable temperature-controlled hot air oven and heat it at a rate of 0.8℃ / min. First, dry it at a drying temperature of 70℃ for 90min, then heat it to 100℃ and hold it for 30min, then heat it to 110℃ and hold it for 75min. Let it cool naturally in the oven to below 40℃ and take it out. Then, rinse the entire filter element with 60℃ deionized water in a reverse flow for 17min. After that, place it in a vacuum drying oven and dry it at a temperature of 60℃ for 100min to obtain the porous adsorption filter element material.

[0027] Comparative Example 1: This comparative example illustrates a method for preparing a porous adsorption filter material, comprising the following steps: Step S1: Weigh out 4.2 parts by weight of 4,4'-oxobis(benzenesulfonyl)hydrazine, 0.8 parts of sodium bicarbonate, 0.06 parts of active zinc oxide, 43 parts of polypropylene powder, 7.5 parts of maleic anhydride-grafted polypropylene, 0.6 parts of antibacterial agent, 0.12 parts of antioxidant 1010, 0.12 parts of antioxidant 168, and 0.6 parts of dicumyl peroxide, and set aside. Step S2: Place 4,4'-oxobisbenzenesulfonyl hydrazine, sodium bicarbonate and active zinc oxide into an agate mortar, grind and mix for 15 minutes, and pass through a 200-mesh sieve to obtain an activated composite pore-forming agent mixture. Step S3: Place polypropylene powder (polypropylene powder model is PPH045) and maleic anhydride grafted polypropylene (maleic anhydride grafted polypropylene model is CMG9801) in a vacuum drying oven and dry at 78℃ for 4 hours. Then add it to a high-speed mixer, add antibacterial agent (antibacterial agent model is RS-CZY), and stir at a stirring speed of 280r / min for 2 minutes. Then add antioxidant 1010 and antioxidant 168, and continue stirring for 3 minutes. Add the activated composite pore-forming agent mixture, and stir at a high speed of 480r / min for 10 minutes. Add dicumyl peroxide, reduce the speed to 180r / min, and stir for 2 minutes to obtain the mixed powder. Step S4: Fill the mixed powder into a 10-inch standard cylindrical filter cartridge mold (outer diameter 65mm, inner diameter 28mm), gently vibrating to release air while filling. Then place the mold in a hydraulic cold pressing molding equipment, set the molding pressure to 3MPa, hold the pressure at room temperature for 5 minutes, release the pressure and demold. Then place it vertically in a programmable temperature-controlled electric curing kiln, introduce high-purity nitrogen to replace the air in the kiln, maintain a nitrogen protective atmosphere throughout the process, raise the temperature from room temperature to 120℃ at a heating rate of 5℃ / min, hold for 20 minutes, then raise the temperature to 155℃ at a heating rate of 2℃ / min, hold for 30 minutes, then raise the temperature to 162℃ at a heating rate of 3℃ / min, hold for 8 minutes, then control the kiln cooling rate to ≤1℃ / min, cool down to room temperature, and obtain the porous adsorption filter cartridge material.

[0028] Comparative Example 2: This comparative example illustrates a method for preparing a porous adsorption filter material, comprising the following steps: Step S1: 2 mol of 4-methylhexahydrophthalic anhydride and 1 mol of 1,6-hexanediol were added to a four-necked flask equipped with a stirrer, thermometer, gas delivery tube, water separator and spherical condenser. Nitrogen gas was introduced for protection, and the mixture was stirred at 140℃ and 230 r / min for 4 h. After that, it was naturally cooled to room temperature to obtain bis(2-carboxy-4-methylcyclohexylformoxy)hexane. Step S2: Add 1 mol of bis(2-carboxy-4-methylcyclohexylformoxy)hexane, 2.05 mol of liquid epoxy resin (model NPEL-128), and 6 g of tetraethylammonium bromide to a four-necked flask equipped with a stirrer, thermometer, gas delivery tube, and spherical condenser. Purge with nitrogen and stir at 115°C and 280 r / min for 2.5 h. Allow to cool naturally to 90°C, add 38 g of propylene glycol methyl ether, stir for 30 min, cool to 68°C, increase the stirring speed to 480 r / min, add 90 g of compound emulsifier (a mixture of emulsifier AEO-9 and Span 60 in a 3 g:1 g ratio), stir for 25 min, then increase the stirring speed to 2000 r / min and add 230 g of the mixture dropwise through a constant pressure dropping funnel. Add 68℃ deionized water, with the first 1 / 3 of the water volume added at a rate of 1 mL / min, then increase the rate to 3 mL / min, and add the remaining deionized water. After the addition is complete, continue stirring for 30 min, allow to cool naturally to room temperature, and filter through a 200-mesh nylon filter to obtain the modified waterborne epoxy resin emulsion. Step S3: Add 20 mL of deionized water to a beaker, adjust the pH to 4.5 by adding acetic acid dropwise, and while stirring at 200 r / min, add 0.8 g of γ-glycidoxypropyltrimethoxysilane. Continue stirring for 20 min, then distill under reduced pressure for 15 min at 40℃ and -0.08 MPa. Next, adjust the pH of 5.3 g of silica sol (HS-830) to 4.5 separately with acetic acid, and then add it dropwise to the beaker. Then, place it in an ultrasonic cleaner, turn on the pulse ultrasonic mode (5s on / 2s off), the power is 200W, and ultrasonicate for 40 minutes under ice bath conditions (1 minute off every 10 minutes of ultrasonication). After ultrasonication, adjust the stirring speed to 280r / min, pour 80g of modified waterborne epoxy resin emulsion into a beaker, stir for 15 minutes, then adjust the pH to 8.8 with ammonia water, add distilled water while stirring, dilute to a solid content of 32%, filter with a 400-mesh nylon filter to obtain an organic-inorganic hybrid emulsion; Step S4: Add 42g of coconut shell activated carbon, 9.6g of diatomaceous earth and 6g of attapulgite to a beaker and stir for 10min at a stirring rate of 280r / min. Then add 600mL of hydrochloric acid solution (molar concentration of hydrochloric acid solution is 4mol / L) and stir for 2h at a temperature of 65℃ and a stirring rate of 330r / min. Filter and wash the filter cake with deionized water until the pH is neutral. Then place it in a vacuum drying oven and dry at a temperature of 78℃ for 6h. Let it cool naturally to room temperature and grind it through a 120-mesh sieve to obtain the acid-washed inorganic filler. Step S5: Weigh the components of the filter element matrix by weight: 4.2 parts of 4,4'-oxobisbenzenesulfonyl hydrazine, 0.8 parts of sodium bicarbonate, 0.06 parts of active zinc oxide, 43 parts of polypropylene powder, 7.5 parts of maleic anhydride-grafted polypropylene, 0.6 parts of antibacterial agent, 0.12 parts of antioxidant 1010, 0.12 parts of antioxidant 168, 4.5 parts of pickled inorganic filler, and 0.6 parts of dicumyl peroxide; Weigh the components of the coating by weight: 60 parts of organic-inorganic hybrid emulsion and 7 parts of water-based epoxy curing agent, for later use; Step S6: Place 4,4'-oxobisbenzenesulfonylhydrazine, sodium bicarbonate and active zinc oxide into an agate mortar, grind and mix for 15 minutes, and pass through a 200-mesh sieve to obtain an activated composite pore-forming agent mixture. Step S7: Place polypropylene powder (polypropylene powder model is PPH045) and maleic anhydride grafted polypropylene (maleic anhydride grafted polypropylene model is CMG9801) in a vacuum drying oven and dry at 78℃ for 4 hours. Then add it to a high-speed mixer, add antibacterial agent (antibacterial agent model is RS-CZY), and stir at a stirring speed of 280r / min for 2 minutes. Then add antioxidant 1010 and antioxidant 168, and continue stirring for 3 minutes. Add the mixture of acid-washed inorganic filler and activated composite pore-forming agent, and stir at a high speed of 480r / min for 10 minutes. Add dicumyl peroxide, reduce the speed to 180r / min, and stir for 2 minutes to obtain the mixed powder. Step S8: Fill the mixed powder into the 10-inch standard cylindrical filter element mold (outer diameter 65mm, inner diameter 28mm), gently vibrate to remove air while filling, then place the mold in a hydraulic cold pressing molding equipment, set the molding pressure to 3MPa, hold the pressure at room temperature for 5 minutes, release the pressure and demold, then place it vertically in a programmable temperature-controlled electric curing kiln, introduce high-purity nitrogen to replace the air in the kiln, maintain a nitrogen protective atmosphere throughout the process, raise the temperature from room temperature to 120℃ at a heating rate of 5℃ / min, hold for 20 minutes, then raise the temperature to 155℃ at a heating rate of 2℃ / min, hold for 30 minutes, then raise the temperature to 162℃ at a heating rate of 3℃ / min, hold for 8 minutes, then control the kiln cooling rate to ≤1℃ / min, cool down to room temperature, and obtain the filter element substrate; Step S9: Treat the filter element substrate with a normal pressure air plasma machine (600W). Keep the spray gun 7cm away from the filter element surface and rotate the filter element at a constant speed of 15r / min. Sweep both sides twice. Use low-pressure air spraying with a 1mm nozzle diameter and an atomization pressure of 0.2MPa. Take an organic-inorganic hybrid emulsion and add a water-based epoxy curing agent (AB-HGA-70) at a stirring rate of 280r / min. Stir for 10 minutes and then spray onto the outer cylindrical surface of the filter element in two coats. Allow each coat to dry at room temperature for 8 minutes before spraying. Spray the next coat, controlling the average thickness of the coating on the outer cylindrical surface to be 25μm after curing. After spraying, place it in a programmable temperature-controlled hot air oven and heat it at a rate of 0.8℃ / min. First, dry it at a drying temperature of 70℃ for 90min, then heat it to 100℃ and hold it for 30min, then heat it to 110℃ and hold it for 75min. Let it cool naturally in the oven to below 40℃ and take it out. Then, rinse the entire filter element with 60℃ deionized water in a reverse flow for 15min. After that, place it in a vacuum drying oven and dry it at a temperature of 55℃ for 90min to obtain the porous adsorption filter element material.

[0029] Comparative Example 3: This comparative example illustrates a method for preparing a porous adsorption filter material, comprising the following steps: Step S1: Add 42g of coconut shell activated carbon, 9.6g of diatomaceous earth and 6g of attapulgite to a beaker and stir for 10min at a stirring rate of 280r / min. Then add 600mL of hydrochloric acid solution (molar concentration of hydrochloric acid solution is 4mol / L) and stir for 2h at a temperature of 65℃ and a stirring rate of 330r / min. Filter and wash the filter cake with deionized water until the pH is neutral. Then place it in a vacuum drying oven and dry at a temperature of 78℃ for 6h. Let it cool naturally to room temperature and grind it through a 120-mesh sieve to obtain acid-washed inorganic filler. Step S2: Adjust the pH of 90g of hydroxyethylidene diphosphonic acid aqueous solution (the mass fraction of hydroxyethylidene diphosphonic acid aqueous solution is 3%) to 4 with citric acid, then add 30g of acid-washed inorganic filler, and ultrasonically impregnate for 30min at a temperature of 48℃, an ultrasonic power of 200W, and an auxiliary stirring rate of 280r / min. Filter the mixture, wash the filter cake 3 times with sodium chloride solution (the molar concentration of sodium chloride solution is 0.2mol / L), and then wash it 6 times with deionized water. Place it in a vacuum drying oven and dry it at a temperature of 68℃ for 4h. Allow it to cool naturally to room temperature, grind it through a 120-mesh sieve to obtain the composite inorganic filler. Step S3: Weigh out 4.2 parts by weight of 4,4'-oxobis(benzenesulfonyl)hydrazine, 0.8 parts of sodium bicarbonate, 0.06 parts of active zinc oxide, 43 parts of polypropylene powder, 7.5 parts of maleic anhydride-grafted polypropylene, 0.6 parts of antibacterial agent, 0.12 parts of antioxidant 1010, 0.12 parts of antioxidant 168, 4.5 parts of composite inorganic filler, and 0.6 parts of dicumyl peroxide, and set aside for later use; Step S4: Place 4,4'-oxobisbenzenesulfonylhydrazine, sodium bicarbonate and active zinc oxide into an agate mortar, grind and mix for 15 minutes, and pass through a 200-mesh sieve to obtain an activated composite pore-forming agent mixture. Step S5: Place polypropylene powder (polypropylene powder model is PPH045) and maleic anhydride grafted polypropylene (maleic anhydride grafted polypropylene model is CMG9801) in a vacuum drying oven and dry at 78℃ for 4 hours. Then add it to a high-speed mixer, add antibacterial agent (antibacterial agent model is RS-CZY), and stir at a stirring speed of 280r / min for 2 minutes. Then add antioxidant 1010 and antioxidant 168, and continue stirring for 3 minutes. Add the mixture of composite inorganic filler and activated composite pore-forming agent, and stir at a high speed of 480r / min for 10 minutes. Add dicumyl peroxide, reduce the speed to 180r / min, and stir for 2 minutes to obtain the mixed powder. Step S6: Fill the mixed powder into the 10-inch standard cylindrical filter element mold (outer diameter 65mm, inner diameter 28mm), gently vibrate to remove air while filling, then place the mold in a hydraulic cold pressing molding equipment, set the molding pressure to 3MPa, hold the pressure at room temperature for 5 minutes, release the pressure and demold, then place it vertically in a programmable temperature-controlled electric curing kiln, introduce high-purity nitrogen to replace the air in the kiln, maintain a nitrogen protective atmosphere throughout the process, raise the temperature from room temperature to 120℃ at a heating rate of 5℃ / min, hold for 20 minutes, then raise the temperature to 155℃ at a heating rate of 2℃ / min, hold for 30 minutes, then raise the temperature to 162℃ at a heating rate of 3℃ / min, hold for 8 minutes, then control the kiln cooling rate to ≤1℃ / min, cool down to room temperature, and obtain the porous adsorption filter element material.

[0030] Performance testing The porous adsorption filter materials of Examples 1-3 and Comparative Examples 1-3 were tested according to the following methods; Heavy metal ions (Pb) 2+ Cd 2+ Removal rate test: The concentration of heavy metal ions in the influent and effluent was determined by inductively coupled plasma optical emission spectrometry (ICP-OES). A Pb solution with an initial concentration of 100 μg / L was prepared using lead nitrate and cadmium nitrate. 2 + Cd 2+Mix the standard solution, adjust the pH to 7.0 with dilute nitric acid, install the filter cartridge vertically in the test device, pre-rinse with pure water at a flow rate of 1 L / min for 10 min, switch to the heavy metal mixed solution, and run continuously at a flow rate of 1 L / min. After running for 1 h, collect 50 mL of influent and effluent water samples respectively, and determine the influent concentration (C0) and effluent concentration (C1) using ICP-OES. The calculation formula is: Removal rate (%) = (C0-C1) / C0×100%.

[0031] Residual chlorine removal rate test: The residual chlorine concentration was determined by N,N-diethyl-p-phenylenediamine spectrophotometry. A residual chlorine standard solution with an initial concentration of 2 mg / L was prepared using sodium hypochlorite. After pre-rinsing the filter cartridge, the residual chlorine solution was introduced at a flow rate of 1 L / min. After running for 1 hour, influent and effluent water samples were collected separately. The absorbance was measured at a wavelength of 515 nm according to the kit instructions, and the residual chlorine concentration was calculated using the same formula as the heavy metal removal rate.

[0032] Weight loss rate test: The scouring resistance of the filter element is evaluated by the weight change of the filter element after continuous water flow. The filter element is vacuum dried at 60℃ to constant weight and the weight is recorded as W0. It is installed in the test device and continuously flushed with pure water at a flow rate of 1L / min for 1000h. The filter element is then removed and vacuum dried again at 60℃ to constant weight and the weight is recorded as W1. The calculation formula is: weight loss rate (%) = (W0-W1) / W0×100%.

[0033] Lifespan test: Simulating actual household usage conditions, the water quality is tested regularly. When the heavy metal removal rate drops below 90%, the lifespan ends. The influent water quality contains Pb. 2+ (100 μg / L), Cd 2+ A mixed solution of 100 μg / L chlorine and 2 mg / L residual chlorine was used to treat 200 L of water per day. The system operated for 8 hours daily, with the remaining water submerged. The effluent quality was tested every 7 days. When two consecutive tests of Pb were performed... 2+ or Cd 2+ When the removal rate is below 90%, stop the test. The cumulative number of days of operation is the service life, which is converted to months (30 days / month).

[0034] Radial compressive strength test: Determine the maximum load-bearing capacity of the filter element under radial compression. Cut a cylindrical specimen with a height of 50 mm from the filter element, place the specimen horizontally between the upper and lower pressure plates of the testing machine, and perform a compression test at a loading speed of 2 mm / min. Record the maximum load F when the specimen fails. Calculation formula: Radial compressive strength (MPa) = F / (L×D), where L is the specimen height (mm) and D is the specimen outer diameter (mm).

[0035] Porosity testing: The porosity of porous materials was determined using mercury porosimetry. Approximately 1g of sample was cut from the filter element and vacuum-dried at 60℃ to constant weight. The weight was recorded as W. The sample was placed in the sample tube of the mercury porosimeter, and a vacuum was drawn to below 1.33 Pa. The pressure was gradually increased to 200 MPa, and the amount of mercury introduced at different pressures was recorded. The instrument automatically calculated the total pore volume V. p Calculation formula: Porosity (%) = V p / (V) p +W / ρ)×100%, where ρ is the density of polypropylene (0.91 g / cm³). 3 ).

[0036] Pure water flux test: Measure the volume of pure water passing through the filter element per unit time and per unit pressure. Install the filter element in the test device and pre-rinse it with pure water for 30 minutes at a pressure of 0.1 MPa. Adjust the pressure to 0.1 MPa and control the temperature at 25℃. Collect the pure water passing through the filter element within 10 minutes and weigh it as M. Calculation formula: Pure water flux (L / h·bar) = (M×6) / (1000×0.1).

[0037] The test results are shown in Tables 1 and 2: Table 1: Test Results Summary Table Table 2: Test Results Summary Table Referring to Tables 1 and 2, based on the comparison between Examples 1-3 and Comparative Examples 1-3, it can be seen that through the synergistic effect of chelated modified composite inorganic fillers and organic-inorganic hybrid coatings, a comprehensive improvement in water purification depth, service life, and mechanical strength is achieved without sacrificing water flux and porosity.

[0038] Based on the comparison between Example 1 and Comparative Example 1, it can be seen that the composite inorganic filler is the core carrier of the filter cartridge's water purification function, and the surface coating is a necessary guarantee for the long-term stable operation of the filter cartridge. Filter cartridges without composite inorganic filler have almost no ability to remove heavy metals and residual chlorine, while filter cartridges without filler or coating have extremely poor resistance to water flow erosion, a high weight loss rate, and a service life of only 6 months.

[0039] Based on the comparison between Example 1 and Comparative Example 2, it can be seen that chelation modification of hydroxyethylidene diphosphonic acid is a key technology for achieving deep purification of heavy metals. Compared with the unmodified physically mixed packing material, the chelated packing material has a significant improvement in the removal rate of lead ions and cadmium ions.

[0040] Based on the comparison between Example 1 and Comparative Example 3, it can be seen that the organic-inorganic hybrid coating can significantly improve the durability and mechanical properties of the filter element. The presence of the surface coating reduces the weight loss rate of the filter element due to water flow erosion and extends its service life. At the same time, it improves the radial compressive strength, effectively solving the pain points of ordinary polypropylene filter elements such as easy powder shedding, easy breakage, and short service life.

[0041] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0042] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in this application, they should all fall within the protection scope of the present invention.

Claims

1. A porous adsorption filter material, characterized in that, Includes a filter element substrate and an organic-inorganic hybrid coating attached to the surface of the filter element substrate; The filter element substrate is prepared from the following components in parts by weight: 4,4'-Oxobis(benzenesulfonyl)hydrazine 4.2-4.8 parts, sodium bicarbonate 0.8-1.0 parts, active zinc oxide 0.06-0.18 parts, polypropylene powder 43-48 parts, maleic anhydride-grafted polypropylene 7.5-9.0 parts, antibacterial agent 0.6-0.7 parts, antioxidant 1010 0.12-0.18 parts, antioxidant 168 0.12-0.18 parts, composite inorganic filler 4.5-6.5 parts, and dicumyl peroxide 0.6-0.8 parts; The organic-inorganic hybrid coating is prepared from the following components in parts by weight: 60-70 parts organic-inorganic hybrid emulsion, 7-8 parts water-based epoxy curing agent; The organic-inorganic hybrid emulsion is prepared by the following steps: Step a1: Mix 4-methylhexahydrophthalic anhydride and 1,6-hexanediol, stir and react, then cool to obtain bis(2-carboxy-4-methylcyclohexylformoxy)hexane; Step a2: Mix bis(2-carboxy-4-methylcyclohexylformoxy)hexane, liquid epoxy resin and tetraethylammonium bromide, stir and react, then add propylene glycol methyl ether and stir, add compound emulsifier and stir, add deionized water dropwise and continue stirring, cool, filter, and obtain modified waterborne epoxy resin emulsion. Step a3: Add deionized water to a beaker, adjust the pH, add γ-glycidoxypropyltrimethoxysilane and stir, distill under reduced pressure, then adjust the pH of the silica sol with acetic acid and add it dropwise to the beaker, then sonicate, pour the modified waterborne epoxy resin emulsion into the beaker, stir, then adjust the pH, add distilled water, filter, and obtain an organic-inorganic hybrid emulsion.

2. The porous adsorption filter material according to claim 1, characterized in that, The ratio of 4-methylhexahydrophthalic anhydride to 1,6-hexanediol in step a1 is 2-2.4 mol: 1-1.2 mol.

3. The porous adsorption filter material according to claim 1, characterized in that, In step a2, the ratio of bis(2-carboxy-4-methylcyclohexylformoxy)hexane, liquid epoxy resin, tetraethylammonium bromide, propylene glycol methyl ether, compound emulsifier, and deionized water is 1-1.2 mol: 2.05-2.46 mol: 6-7.2 g: 38-45.6 g: 90-108 g: 230-280 g; the compound emulsifier is a mixture of emulsifier AEO-9 and Span 60 in a ratio of 3 g: 1 g.

4. The porous adsorption filter material according to claim 1, characterized in that, The ratio of deionized water, γ-glycidyl etheroxypropyltrimethoxysilane, silica sol, and modified waterborne epoxy resin emulsion in step a3 is 20-22 mL: 0.8-0.9 g: 5.3-5.9 g: 80-90 g.

5. The porous adsorption filter material according to claim 1, characterized in that, The composite inorganic filler is prepared by the following steps: Step b1: Add coconut shell activated carbon, diatomaceous earth and attapulgite to a beaker and stir. Then add hydrochloric acid solution, stir to react, filter, wash, dry, cool, grind and sieve to obtain acid-washed inorganic filler. Step b2: Adjust the pH of the aqueous solution of hydroxyethylidene diphosphonic acid with citric acid, then add the acid-washed inorganic packing, ultrasonically impregnate, filter, wash the filter cake with sodium chloride solution, wash with deionized water, dry, cool, grind and sieve to obtain the composite inorganic packing.

6. The porous adsorption filter material according to claim 5, characterized in that, In step b1, the ratio of coconut shell activated carbon, diatomaceous earth, attapulgite, and hydrochloric acid solution is 42-44g: 9.6-10g: 6-6.3g: 600-800mL; the molar concentration of the hydrochloric acid solution is 4mol / L.

7. The porous adsorption filter material according to claim 5, characterized in that, In step b2, the ratio of the aqueous solution of hydroxyethylidene diphosphonic acid to the acid-washed inorganic filler is 90-96g: 30-32g.

8. The porous adsorption filter material according to claim 5, characterized in that, The molar concentration of the sodium chloride solution in step b2 is 0.2 mol / L; the mass fraction of the hydroxyethylidene diphosphonic acid aqueous solution is 3%.

9. A method for preparing a porous adsorption filter material, characterized in that, The preparation of the porous adsorption filter material as described in any one of claims 1-8 includes the following steps: Step 1: Weigh the following components by weight for the filter element matrix: 4,4'-oxobisbenzenesulfonyl hydrazine 4.2-4.8 parts, sodium bicarbonate 0.8-1.0 parts, active zinc oxide 0.06-0.18 parts, polypropylene powder 43-48 parts, maleic anhydride-grafted polypropylene 7.5-9.0 parts, antibacterial agent 0.6-0.7 parts, antioxidant 1010 0.12-0.18 parts, antioxidant 168 0.12-0.18 parts, composite inorganic filler 4.5-6.5 parts, and dicumyl peroxide 0.6-0.8 parts; Weigh the following components by weight for the coating: organic-inorganic hybrid emulsion 60-70 parts, water-based epoxy curing agent 7-8 parts, for later use; Step 2: Grind and mix 4,4'-oxobisbenzenesulfonyl hydrazine, sodium bicarbonate and active zinc oxide, and sieve to obtain an activated composite pore-forming agent mixture; Step 3: Dry the polypropylene powder and maleic anhydride-grafted polypropylene, then add them to a high-speed mixer, add antibacterial agent and stir, then add antioxidant 1010 and antioxidant 168, continue stirring, add the mixture of composite inorganic filler and activated composite pore-forming agent, stir at high speed, add dicumyl peroxide and stir to obtain mixed powder. Step 4: Fill the mold with the mixed powder, then place the mold in a hydraulic cold pressing molding equipment, maintain pressure, release pressure and demold, then place it vertically in a program-controlled temperature electric curing kiln, and then cool it down to obtain the filter element substrate; Step 5: Treat the filter element substrate with an atmospheric pressure air plasma machine, and then use a low-pressure air spraying method to take an organic-inorganic hybrid emulsion, add a water-based epoxy curing agent, stir, and spray it onto the outer cylindrical surface of the filter element. Then place it in a program-controlled temperature hot air oven to dry and cool. After that, rinse the entire filter element with deionized water and then dry it to obtain a porous adsorption filter element material.

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