Antibacterial filter material, preparation method thereof, filter element and water purification equipment

Abstract

The invention discloses an antibacterial filter material, a preparation method thereof, a filter element and water purification equipment, and relates to the technical field of purification. The antibacterial filter material comprises an antibacterial filter screen or an antibacterial carbon rod, the antibacterial filter screen comprises a filter screen base body, the filter screen base body is of a net structure, and first modified antibacterial agents are arranged in the filter screen base body and on the surface of the filter screen base body; the antibacterial carbon rod comprises a carbon rod base body, pore structures are arranged in the carbon rod base body and on the surface of the carbon rod base body, and a second modified antibacterial agent is arranged in the carbon rod base body and on the surface of the carbon rod base body. A conventional antibacterial agent is replaced by the first modified antibacterial agent or the second modified antibacterial agent with charges on the surface, and due to the fact that the surface of the first modified antibacterial agent or the second modified antibacterial agent is charged, agglomeration among antibacterial agent molecules can be reduced through electrostatic repulsive force, the antibacterial agent is dispersed more uniformly, and the antibacterial effect is better. And the interaction between the antibacterial agent and bacteria can be enhanced, so that compared with the conventional antibacterial filter material, the antibacterial filter material disclosed by the invention can remarkably improve the antibacterial effect.

Description

Technical Field

[0001] The present invention relates to the field of purification technology, and in particular to an antibacterial filter material and a preparation method thereof, a filter element and a water purification device. Background Art

[0002] The filter element is one of the important components of water purification equipment. The filter element of household water purification equipment usually intercepts microorganisms and bacteria in the water source through the RO membrane. After long-term use, a large number of microorganisms and other pollutants will accumulate on the filter element, which will not only clog the membrane pores, but also cause membrane pollution and affect the water quality. Bacterial growth will also destroy the desalination layer structure and cause the RO membrane to emit odor. At present, there are many ways to sterilize and antibacterial filter elements on the market: (1) Most of the sterilization treatment is carried out by pre-loading silver activated carbon, so that the water source entering the RO filter element is sterile or has a low bacterial concentration. The health and safety standards limit the increase in silver ion precipitation in drinking water to ≤0.005mg / L. Therefore, conventional silver activated carbon materials that meet health and safety standards will control the silver ion addition to about 0.1%, which greatly limits the sterilization effect and thus only plays an antibacterial role; (2) Antibacterial modification is performed on the RO membrane, such as using quaternary ammonium salts to modify the membrane surface. This modification method is expensive and affects the water flux and desalination rate, resulting in unstable basic performance of the filter element. (3) During the process of rolling the membrane element, replacing the filter screen between the membrane sheets with an antibacterial filter screen can also improve the bactericidal and antibacterial ability. The antibacterial filter screen is usually made by adding antibacterial agent masterbatch (such as zinc oxide masterbatch) to polymer raw materials (such as polypropylene). Although the cost of making antibacterial filter screens is low and does not affect the subsequent overall filter element structure and the performance of RO membrane elements, the antibacterial performance of existing antibacterial filter screens is very unstable and sometimes not. Most of the antibacterial filter materials in the same batch do not have antibacterial properties, and only a small part of them have antibacterial properties.

[0003] In the field of commercial filter elements, the catering industry usually uses filter elements with large flux and high total water purification volume, but the filtration accuracy of such filter elements is low and they cannot effectively intercept E. coli. In order to improve the problem of being unable to effectively intercept E. coli, commercial filter elements often use multi-stage filtration and sterilize by ultraviolet light sterilization in the last stage, but the installation and maintenance of multi-stage filter element systems are relatively complicated and require larger installation space and maintenance. Currently, researchers are committed to using other antibacterial filter materials (such as silver-loaded carbon rods or silver-loaded granular carbon) as alternatives to multi-stage filter elements, but silver-loaded carbon rods or silver-loaded granular carbon may precipitate a large amount of silver ions during use. The health and safety standards limit the increase in silver ion precipitation in drinking water to ≤0.005 mg / L. Therefore, conventional silver-loaded carbon rods or silver-loaded granular carbon materials that meet health and safety standards will control the amount of silver ions added to about 0.1%, and their bactericidal effect is very limited, and they only have an antibacterial effect.

[0004] Therefore, in the field of purification, an antibacterial filter material with good antibacterial properties is still to be developed to improve the sterilization effect of the filter element. Summary of the Invention

[0005] The main purpose of the present invention is to provide an antibacterial filter material and a preparation method thereof, a filter element and a water purification device, aiming to solve the problem of poor antibacterial performance of existing antibacterial filter materials.

[0006] To achieve the above objectives, the present invention provides an antibacterial filter material for use in a filter element of a water purification device, the antibacterial filter material comprising an antibacterial filter screen, the antibacterial filter screen comprising a filter screen matrix having a mesh structure, and a first modified antibacterial agent disposed within and on the surface of the filter screen matrix;

[0007] The first modified antibacterial agent includes a first metal oxide antibacterial agent and an encapsulating agent connected to the first metal oxide antibacterial agent through a chemical bond, and the surface of the encapsulating agent has a positive charge or a negative charge.

[0008] In one embodiment, the surface of the encapsulating agent is positively charged, and the Zeta potential of the first modified antimicrobial agent is 30 mV to 35 mV; and / or,

[0009] The surface of the encapsulating agent is negatively charged, and the Zeta potential of the first modified antimicrobial agent is -25mV to -30mV; and / or,

[0010] The surface of the encapsulating agent is positively charged, and the encapsulating agent comprises a cationic organic compound; and / or,

[0011] The surface of the encapsulating agent is negatively charged, and the encapsulating agent comprises carboxylic acid and its derivatives.

[0012] In one embodiment, the antibacterial filter material is an antibacterial filter mesh:

[0013] The surface of the encapsulating agent is positively charged, and the encapsulating agent comprises a quaternary ammonium salt; wherein the quaternary ammonium salt comprises at least one of tetramethylammonium bromide, dodecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, behenyltrimethylammonium bromide, dihexadecyldimethylammonium bromide, ditetradecyldimethylammonium bromide and dioctadecyldimethylammonium bromide; and / or,

[0014] The surface of the encapsulating agent is negatively charged, and the encapsulating agent comprises citric acid.

[0015] The present invention provides an antibacterial filter material for a filter element of a water purification device, wherein the antibacterial filter material comprises an antibacterial carbon rod, wherein the antibacterial carbon rod comprises a carbon rod matrix, wherein the interior and surface of the carbon rod matrix are provided with a pore structure, and a second modified antibacterial agent is provided within and on the surface of the carbon rod matrix;

[0016] The second modified antibacterial agent includes a second metal oxide antibacterial agent and an encapsulating agent connected to the second metal oxide antibacterial agent through a chemical bond, and the surface of the encapsulating agent has a positive charge or a negative charge.

[0017] In one embodiment, the antibacterial filter material is an antibacterial carbon rod:

[0018] The surface of the encapsulating agent is positively charged, and the Zeta potential of the second modified antimicrobial agent is 30mV to 37mV; and / or,

[0019] The surface of the encapsulating agent is negatively charged, and the Zeta potential of the modified antibacterial agent is -21mV to -26mV; and / or,

[0020] The surface of the encapsulating agent is positively charged, and the encapsulating agent comprises a cationic organic compound; and / or,

[0021] The surface of the encapsulating agent is negatively charged, and the encapsulating agent comprises carboxylic acid and its derivatives.

[0022] In one embodiment, the antibacterial filter material is an antibacterial carbon rod:

[0023] The surface of the encapsulating agent is positively charged, and the cationic organic compound includes a quaternary ammonium salt; wherein the quaternary ammonium salt includes at least one of tetramethylammonium bromide, dodecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, behenyltrimethylammonium bromide, dihexadecyldimethylammonium bromide, ditetradecyldimethylammonium bromide and dioctadecyldimethylammonium bromide; and / or,

[0024] The surface of the encapsulating agent is negatively charged, and the encapsulating agent comprises citric acid.

[0025] The present invention provides a method for preparing the antibacterial filter material, wherein the antibacterial filter material is an antibacterial filter mesh, and the method for preparing the antibacterial filter material comprises the following steps:

[0026] A filter matrix material is provided, the filter matrix material is mixed with a first modified antibacterial agent, and the mixture is melted and extruded into a mesh to obtain an antibacterial filter material.

[0027] In one embodiment, the antibacterial filter material is an antibacterial filter mesh, and the first modified antibacterial agent is prepared by the following steps:

[0028] The first metal oxide antibacterial agent, the encapsulating agent, the hydroxylation agent and water are mixed and subjected to a hydrothermal reaction to obtain a first modified antibacterial agent.

[0029] In one embodiment, the antibacterial filter material is an antibacterial filter mesh:

[0030] The molar ratio of the metal oxide antibacterial agent to the encapsulating agent is (0.9-1): (0.02-0.06); and / or,

[0031] The hydroxylation agent includes ethylene glycol, and the mass ratio of the metal oxide antibacterial agent to the ethylene glycol is 1: (10-15).

[0032] In one embodiment, the antibacterial filter material is an antibacterial filter screen, and the steps of providing a filter screen matrix material, mixing the filter screen matrix material with a first modified antibacterial agent, melting, and extruding the mixture into a mesh to obtain the antibacterial filter material include:

[0033] The first modified antibacterial agent is mixed with a carrier material and then extruded and granulated to obtain an antibacterial masterbatch;

[0034] A filter matrix material is provided, the filter matrix material is mixed with the antibacterial masterbatch, and the mixture is melted and extruded into a mesh to obtain an antibacterial filter material.

[0035] In one embodiment, the antibacterial filter material is an antibacterial filter mesh:

[0036] The filter matrix is ​​made of thermoplastic plastic, and the carrier material includes thermoplastic plastic or degradable material; wherein the thermoplastic plastic includes any one of polypropylene and polyethylene, and the degradable material includes at least one of polylactic acid, polyvinyl alcohol, starch-based polymer, polybutylene succinate, polyhydroxyalkanoate and polycaprolactone; and / or,

[0037] The mass ratio of the first modified antimicrobial agent to the carrier material is 1:(4-5); and / or,

[0038] The mass ratio of the filter matrix raw material to the antibacterial masterbatch is (20-30):1.

[0039] The present invention provides a method for preparing the antibacterial filter material, wherein the antibacterial filter material is an antibacterial carbon rod, and the method for preparing the antibacterial filter material comprises the following steps:

[0040] A carbon rod matrix raw material powder, a second modified antibacterial agent powder and a binder are provided, the carbon rod matrix raw material powder, the second modified antibacterial agent powder and the binder are mixed, and then pressed, baked and sintered to obtain an antibacterial carbon rod.

[0041] In one embodiment, the antibacterial filter material is an antibacterial carbon rod, and the second modified antibacterial agent powder is prepared by the following steps:

[0042] An inorganic metal salt, a coating agent, a hydroxylating agent and a complexing agent are mixed and subjected to a hydrothermal reaction to obtain a metal oxide gel. The metal oxide gel is cleaned and dried, and ground to obtain a second modified antibacterial agent powder; wherein the inorganic metal salt includes an inorganic zinc salt or an inorganic copper salt.

[0043] In one embodiment, the antibacterial filter material is an antibacterial carbon rod:

[0044] The molar ratio of the inorganic metal salt to the encapsulating agent is (0.8-1): (0.04-0.06); and / or,

[0045] The hydroxylation agent includes ethylene glycol, the complexing agent includes ammonia water, the mass concentration of the inorganic metal salt in the hydroxylation agent is 0.2-0.45 g / mL, and the volume ratio of the ethylene glycol to the ammonia water is (100-120): (3-6).

[0046] In one embodiment, the antibacterial filter material is an antibacterial carbon rod:

[0047] The mass ratio of the carbon rod matrix raw material powder, the second modified antibacterial agent powder and the binder is 100: (0.1-2): (5-12); and / or,

[0048] Before mixing the inorganic metal salt, the encapsulating agent, the hydroxylating agent and the complexing agent, the second modified antimicrobial agent powder is passed through a 30-50 mesh sieve.

[0049] The present invention provides a filter element, which includes the antibacterial filter material described in the aforementioned technical solution, or includes the antibacterial filter material prepared according to the preparation method of the antibacterial filter material described in the aforementioned technical solution.

[0050] The present invention provides a water purification device, which includes the filter element.

[0051] The beneficial effects of the technical solution of the present invention are as follows:

[0052] The technical solution of the present invention provides an antibacterial filter material, comprising an antibacterial filter, the antibacterial filter comprising a filter matrix, the filter matrix having a first modified antibacterial agent disposed both within and on the surface of the filter matrix, the surface of the first modified antibacterial agent having an electric charge. The technical solution of the present invention uses an antibacterial agent modified with an encapsulating agent instead of a conventional unmodified antibacterial agent. Due to the positive or negative charge on the surface of the first modified antibacterial agent, during subsequent processing, the electrostatic interaction between the first modified antibacterial agent and the mold can increase the concentration of the antibacterial agent on the surface of the filter matrix. Compared to conventional antibacterial filter materials using unmodified antibacterial agents, the antibacterial filter material provided by the present invention increases the concentration of the antibacterial agent on the surface of the filter matrix, thereby increasing the likelihood of the antibacterial agent contacting bacteria and effectively enhancing the antibacterial effect of the antibacterial filter material. At the same time, due to the electrostatic repulsion between the molecules of the first modified antibacterial agent, the agglomeration of the antibacterial agent molecules is reduced, making the antibacterial agent more evenly distributed in the filter matrix, further enhancing the antibacterial effect. Furthermore, the charge on the surface of the first modified antimicrobial agent enhances the interaction between the antimicrobial agent and bacteria, further improving the antimicrobial efficacy of the antimicrobial agent. Therefore, the antimicrobial filter material provided by the present invention has excellent bactericidal properties while having minimal impact on water flux and salt rejection, effectively resolving the issues of unstable antimicrobial performance and poor antimicrobial efficacy of existing antimicrobial filters.

[0053] The technical solution of the present invention also provides an antibacterial filter material, which includes an antibacterial carbon rod, which includes a carbon rod matrix, the interior and surface of the carbon rod matrix are provided with a porous structure, and the interior and surface of the carbon rod matrix are provided with a second modified antibacterial agent. Due to the positive or negative charge on the surface of the second modified antibacterial agent, not only can the agglomeration of antibacterial agent molecules be reduced through the electrostatic repulsion between molecules, making the distribution of the antibacterial agent more uniform in the carbon rod matrix, but it can also enhance the interaction between the antibacterial agent and bacteria, thereby effectively improving the antibacterial effect of the antibacterial filter material. The antibacterial filter material provided by the present invention has excellent bactericidal properties and can be used to solve the problem of poor antibacterial performance of existing antibacterial carbon rods. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0055] Figure 1 Schematic diagram of the structure of the antibacterial filter material provided in Example 2 and Comparative Example 2 of the present invention.

[0056] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0057] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0058] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0059] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of such features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0060] There are many ways to sterilize and antibacterial filter elements of household water purification equipment on the market: (1) Most of the sterilization treatment is done by pre-silver-loaded activated carbon, but the sterilization effect of pre-silver-loaded activated carbon is very limited because it only plays an antibacterial role; (2) Antibacterial modification is performed on the RO membrane, but the cost of this modification method is high and it will affect the water flux and desalination rate; (3) In the process of rolling the membrane element, an antibacterial filter is used to separate the membranes to improve the sterilization and antibacterial ability. The antibacterial filter material is usually made by adding antibacterial agent masterbatch (such as zinc oxide masterbatch) to polymer raw materials (such as polypropylene). Although the cost of making antibacterial filter materials is low and does not affect the subsequent overall filter element structure and the performance of RO membrane elements, the antibacterial performance of existing antibacterial filter screens is very unstable and sometimes not. Most of the antibacterial filter materials in the same batch do not have antibacterial properties, and only a small part of them have antibacterial properties. The main reason is that the zinc oxide is wrapped in PP material. The structural diagram is as shown in the figure. Figure 1 As shown, the antibacterial agent cannot be exposed on the filter surface over a large area, so a stable and ideal antibacterial effect cannot be achieved.

[0061] The catering industry typically uses filter cartridges with large flow rates and high total water purification volume, but the filtration accuracy of these filter cartridges is low and they cannot effectively intercept E. coli. To improve the problem of being unable to effectively intercept E. coli, commercial filter cartridges often use multi-stage filtration and sterilize by ultraviolet light sterilization in the last stage. However, the installation and maintenance of multi-stage filter cartridge systems are relatively complicated and require larger installation space and maintenance. Currently, researchers are trying to use other antibacterial filter materials (such as silver-loaded carbon rods or silver-loaded granular carbon) as alternatives to multi-stage filter cartridges. However, silver-loaded carbon rods or silver-loaded granular carbon may release a large amount of silver ions during use, and the bactericidal effect is very limited, and they only have an antibacterial effect. In response to health and safety standards, many antibacterial agent suppliers have tried to use plant antibacterial agents to make plant antibacterial carbon rods. However, because plant antibacterial agents are not resistant to high temperatures, they will produce an odor (burned plant odor) during the firing process due to overburning of the plant antibacterial agent. This odor will be emitted into the water body, and there is currently no effective solution. Therefore, in the field of purification, an antibacterial filter material with good antibacterial properties is still to be developed to improve the sterilization effect of the filter element.

[0062] Based on the above background, the present invention proposes an antibacterial filter material for use in a filter element of a water purification device. Figure 1 The antibacterial filter material includes an antibacterial filter screen, the antibacterial filter screen includes a filter screen matrix, the filter screen matrix forms a mesh structure, and the interior and surface of the filter screen matrix are provided with a first modified antibacterial agent;

[0063] The first modified antibacterial agent includes a first metal oxide antibacterial agent and an encapsulating agent connected to the first metal oxide antibacterial agent through a chemical bond, and the surface of the encapsulating agent has a positive charge or a negative charge.

[0064] In the technical solution of the present invention, an antibacterial agent modified with a coating agent is used instead of a conventional unmodified antibacterial agent. Due to the positive or negative charge on the surface of the first modified antibacterial agent, during the subsequent processing, the electrostatic correlation between the first modified antibacterial agent and the mold can increase the enrichment of the antibacterial agent on the surface of the filter matrix. Compared with the conventional antibacterial filter material using an unmodified antibacterial agent, the antibacterial filter material provided by the present invention increases the enrichment of the antibacterial agent on the surface of the filter matrix, thereby increasing the possibility of contact between the antibacterial agent and bacteria, and effectively improving the antibacterial effect of the antibacterial filter material. At the same time, due to the electrostatic repulsion between the molecules of the first modified antibacterial agent, the agglomeration phenomenon between the molecules of the antibacterial agent is reduced, so that the antibacterial agent is more evenly distributed in the filter matrix, further improving the antibacterial effect. In addition, the charge on the surface of the first modified antibacterial agent can also enhance the interaction between the antibacterial agent and bacteria, which is conducive to further improving the antibacterial effect of the antibacterial agent. Therefore, the antibacterial filter material provided by the present invention has excellent bactericidal performance and has little effect on water flux and desalination rate. It can effectively solve the problems of unstable antibacterial performance and poor antibacterial effect of existing antibacterial filters and has good application prospects.

[0065] In an embodiment of the present invention, the antimicrobial filter material is an antimicrobial filter screen, and the first modified antimicrobial agent covers no less than 10% of the surface area of ​​the filter screen substrate. By providing no less than 10% coverage of the first modified antimicrobial agent on the surface of the filter screen substrate, more antimicrobial agent is present on the surface of the filter screen substrate, thereby increasing direct contact areas with bacteria and other microorganisms. This improves the overall antimicrobial performance of the filter screen, allowing the filter screen to maintain its antimicrobial activity for a longer period of time during its service life.

[0066] It should be noted that, in this article, the coverage area of ​​the first modified antimicrobial agent on the surface of the filter matrix is ​​obtained by analogy based on the results of the inhibition zone experiment of Escherichia coli. The process is as follows:

[0067] The inhibition zone experiment was carried out using zinc oxide that had passed through 20 mesh / 50 mesh / 100 mesh / 120 mesh / 150 mesh sieves, and the range of the bacterial zone was 8.5mm / 9.5mm / 10mm / 10mm / 10mm respectively. According to the approximate calculation of the maximum cross-sectional area of ​​zinc oxide particles / area of ​​inhibition zone, the inhibition zone result of zinc oxide with the highest fineness (passing through 150 mesh sieve) was compared with the agglomerated nano-zinc oxide. One square meter requires 12,738 inhibition zones, which is equivalent to 12,738 dispersed nano-zinc oxides. Combined with the bacterial zone range, it is estimated that the proportion of antibacterial agents is about 10%.

[0068] Covering a large area with antibacterial agent may cause other problems, such as making the filter mesh frizzy, easily scratching the membrane during the production process, affecting the desalination rate, reducing the lifespan, etc. Moreover, the more antibacterial agent, the higher the preparation cost. The technicians of the present invention can comprehensively consider the bactericidal effect, production cost and filtration requirements to adjust the coverage area of ​​the modified antibacterial agent on the surface of the filter mesh substrate.

[0069] In an embodiment of the present invention, the antibacterial filter material is an antibacterial filter mesh, and when the surface of the coating agent is positively charged, the Zeta potential of the modified antibacterial agent is 30mV to 35mV. Compared with the unmodified antibacterial agent, the surface of the modified antibacterial agent is charged. The electrostatic repulsion between the antibacterial agent molecules can reduce the agglomeration of the antibacterial agent, making the antibacterial agent more evenly distributed in the filter mesh matrix. Therefore, the surface charge strength of the modified antibacterial agent will affect the dispersion of the antibacterial agent inside and on the surface of the filter mesh matrix; secondly, during the preparation of the filter mesh, the charge strength of the coating agent surface may affect the enrichment degree of the modified antibacterial agent on the surface of the filter mesh matrix; in addition, the cell walls and cell membranes of most bacteria are negatively charged. The positively charged antibacterial agent can make the antibacterial agent more easily adhere to the bacterial surface through electrostatic attraction, thereby improving the sterilization efficiency. In addition, the strong positive charge of the antibacterial agent also helps it penetrate the bacterial cell wall. The technical solution of the present invention sets the Zeta potential of the modified antibacterial agent within the above range, which is beneficial to meeting the antibacterial requirements of the filter and controlling the amount of the coating agent.

[0070] In an embodiment of the present invention, the antimicrobial filter material is an antimicrobial filter mesh, and when the surface of the coating agent is negatively charged, the zeta potential of the first modified antimicrobial agent is -25 mV to -30 mV. Setting the zeta potential of the modified antimicrobial agent within this range can produce an antimicrobial filter material with excellent antimicrobial properties while also taking production costs into consideration.

[0071] In an embodiment of the present invention, the antimicrobial filter material is an antimicrobial filter mesh, the surface of the coating agent is positively charged, and the coating agent comprises a cationic organic compound. Cationic organic compounds themselves generally have good antimicrobial activity, and modifying the antimicrobial agent with a cationic organic compound can further enhance the antimicrobial effect of the antimicrobial agent.

[0072] Further, in an embodiment of the present invention, the antibacterial filter material is an antibacterial filter screen, and the coating agent includes a quaternary ammonium salt; wherein the quaternary ammonium salt includes at least one of tetramethylammonium bromide, dodecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, behenyltrimethylammonium bromide, dihexadecyldimethylammonium bromide, ditetradecyldimethylammonium bromide and dioctadecyldimethylammonium bromide. Quaternary ammonium salt materials have efficient antibacterial activity, good chemical stability, and the advantages of being difficult to volatilize or decompose in most cases. Moreover, quaternary ammonium salts generally have good surface activity, which helps the inorganic antibacterial agent to be evenly dispersed in the polymer matrix and reduce agglomeration. In one embodiment of the present invention, hexadecyltrimethylammonium chloride (CTAC) with a longer chain is selected as the coating agent, which has suitable hydrophobicity, can make the antibacterial agent evenly dispersed in the filter screen matrix, and has good compatibility with the filter screen matrix material.

[0073] In an embodiment of the present invention, the antibacterial filter material is an antibacterial filter mesh, and when the surface of the coating agent is negatively charged, the coating agent comprises carboxylic acid and its derivatives. Carboxylic acid groups are easily chemically modified and can be combined with other functional groups through esterification, amidation, and other reactions. Furthermore, the modified antibacterial agent forms electrostatic, hydrogen bonding, and hydrophobic interactions with bacteria through the carboxylic acid groups, thereby enhancing the interaction between the antibacterial agent and bacteria and improving antibacterial performance.

[0074] Furthermore, in an embodiment of the present invention, the antibacterial filter material is an antibacterial filter mesh, and the coating agent includes citric acid. Using citric acid to modify the antibacterial agent facilitates obtaining a modified antibacterial agent with high electronegativity. Citric acid also contains abundant hydroxyl and carboxyl functional groups, which can form hydrogen bonds and hydrophilic-hydrophobic interactions with bacteria, enhancing the interaction between the antibacterial agent and bacteria, and thereby enhancing the antibacterial effect of the antibacterial agent.

[0075] The present invention also provides an antibacterial filter material for a filter element of a water purification device, the antibacterial filter material comprising an antibacterial carbon rod, the antibacterial carbon rod comprising a carbon rod matrix, the interior and surface of the carbon rod matrix are provided with a pore structure, and the interior and surface of the carbon rod matrix are provided with a second modified antibacterial agent;

[0076] The second modified antibacterial agent includes a second metal oxide antibacterial agent and an encapsulating agent connected to the second metal oxide antibacterial agent through a chemical bond, and the surface of the encapsulating agent has a positive charge or a negative charge.

[0077] In the technical solution of the present invention, the antibacterial filter material includes an antibacterial carbon rod, which includes a carbon rod matrix, the interior and surface of the carbon rod matrix are provided with a porous structure, and the interior and surface of the carbon rod matrix are provided with a second modified antibacterial agent. Due to the positive or negative charge on the surface of the second modified antibacterial agent, not only can the agglomeration of antibacterial agent molecules be reduced through the electrostatic repulsion between molecules, making the distribution of the antibacterial agent more uniform in the carbon rod matrix, but it can also enhance the interaction between the antibacterial agent and bacteria, thereby effectively improving the antibacterial effect of the antibacterial filter material. The antibacterial filter material provided by the present invention has excellent bactericidal properties and can be used to solve the problem of poor antibacterial performance of existing antibacterial carbon rods.

[0078] In an embodiment of the present invention, the antimicrobial filter material is an antimicrobial carbon rod, and when the surface of the coating agent is positively charged, the zeta potential of the modified antimicrobial agent is 30mV to 37mV. Setting the zeta potential of the modified antimicrobial agent within this range helps control the amount of coating agent used and production costs while meeting the antimicrobial requirements of the filter.

[0079] In an embodiment of the present invention, the antimicrobial filter material is an antimicrobial carbon rod, and when the surface of the coating agent is negatively charged, the zeta potential of the first modified antimicrobial agent is between -21 mV and -26 mV. Setting the zeta potential of the modified antimicrobial agent within this range can produce an antimicrobial filter material with excellent antimicrobial properties while also considering production costs.

[0080] In an embodiment of the present invention, the antimicrobial filter material is an antimicrobial carbon rod, the surface of the coating agent is positively charged, and the coating agent comprises a cationic organic compound. Cationic organic compounds themselves generally have good antimicrobial activity, and using a cationic organic compound as a modified antimicrobial agent can further enhance the antimicrobial effect of the antimicrobial agent.

[0081] Furthermore, in an embodiment of the present invention, the antibacterial filter material is an antibacterial carbon rod mesh, and the coating agent includes a quaternary ammonium salt; wherein the quaternary ammonium salt includes at least one of tetramethylammonium bromide, dodecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, behenyltrimethylammonium bromide, dihexadecyldimethylammonium bromide, ditetradecyldimethylammonium bromide, and dioctadecyldimethylammonium bromide. Quaternary ammonium salt materials have high antibacterial activity and good chemical stability.

[0082] In an embodiment of the present invention, the antibacterial filter material is an antibacterial carbon rod, and the surface of the coating agent is negatively charged, and the coating agent includes carboxylic acid and its derivatives. Carboxylic acid groups are easily chemically modified and can be combined with other functional groups through esterification, amidation, and other reactions. Moreover, the modified antibacterial agent forms electrostatic, hydrogen bonding, and hydrophobic interactions with bacteria through the carboxylic acid groups, which can enhance the interaction between the antibacterial agent and bacteria, thereby improving antibacterial performance.

[0083] Furthermore, in an embodiment of the present invention, the antibacterial filter material is an antibacterial carbon rod, and the coating agent includes citric acid. Using citric acid to modify the antibacterial agent facilitates obtaining a modified antibacterial agent with high electronegativity. Furthermore, citric acid contains abundant hydroxyl and carboxyl functional groups, which can form hydrogen bonds and hydrophilic-hydrophobic interactions with bacteria, enhancing the interaction between the antibacterial agent and bacteria, thereby enhancing the antibacterial effect of the antibacterial agent.

[0084] The present invention also provides a method for preparing the antibacterial filter material, wherein the antibacterial filter material is an antibacterial filter mesh, and the method for preparing the antibacterial filter material comprises the following steps:

[0085] A filter matrix material is provided, the filter matrix material is mixed with a first modified antibacterial agent, and then smelted and extruded into a mesh to obtain an antibacterial filter material.

[0086] The present invention adopts a conventional preparation method to prepare an antibacterial filter. First, the filter matrix raw material is mixed with a first modified antibacterial agent, and then smelted and extruded into a mesh to obtain a filter matrix with a mesh structure. At the same time, the first modified antibacterial agent is dispersed in the filter matrix, wherein a portion of the modified antibacterial agent migrates to the surface of the filter matrix. Compared with conventional antibacterial filter materials (most of the antibacterial agents are wrapped inside the filter matrix), the enrichment degree of the antibacterial agent on the filter surface can be increased, thereby providing more antibacterial agent to contact bacteria, significantly improving the antibacterial effect of the filter. Moreover, compared with conventional antibacterial agents, the first modified antibacterial agent of the present invention reduces the agglomeration between antibacterial agent molecules, can be evenly dispersed in the filter matrix, and at the same time enhances the interaction between the antibacterial agent and bacteria, thereby further improving the antibacterial effect of the antibacterial filter.

[0087] In an embodiment of the present invention, the antibacterial filter material is an antibacterial filter mesh, and the first modified antibacterial agent is prepared by the following steps:

[0088] The first metal oxide antibacterial agent, the encapsulating agent, the hydroxylation agent and water are mixed and subjected to a hydrothermal reaction to obtain a first modified antibacterial agent.

[0089] During the hydrothermal treatment, a hydroxylation agent is used to modify hydroxyl groups on the surface of the metal oxide antimicrobial agent, with water serving as the reaction medium. After the antimicrobial agent modifies the hydroxyl groups, the encapsulating agent chemically reacts with the hydroxyl groups on the antimicrobial agent to form a chemical bond, thereby attaching to the antimicrobial agent.

[0090] In an embodiment of the present invention, the step of mixing the first metal oxide antibacterial agent, the encapsulating agent, the hydroxylating agent and water and performing a hydrothermal reaction to obtain the first modified antibacterial agent comprises:

[0091] mixing a first metal oxide antibacterial agent, a coating agent, a hydroxylation agent and water, and performing a hydrothermal reaction to obtain a first hydrothermal reaction product;

[0092] The first hydrothermal reaction product is centrifuged to obtain a solid, which is then washed with ethanol and water in sequence, and dried at 100° C. to obtain a first modified antibacterial agent.

[0093] In an embodiment of the present invention, the metal oxide antimicrobial agent comprises at least one of zinc oxide and copper oxide. Metal oxide antimicrobial agents have the advantages of good heat resistance, high chemical stability, and long-lasting antimicrobial properties. Compared to inorganic metal ion antimicrobial agents, metal oxide antimicrobial agents have higher chemical stability and are less prone to unnecessary chemical reactions, which helps ensure the durability and consistency of the antimicrobial effect. Furthermore, metal oxide antimicrobial agents can maintain structural and functional stability at higher temperatures, making them suitable for use in high-temperature processing techniques.

[0094] Furthermore, in an embodiment of the present invention, the metal oxide antimicrobial agent is zinc oxide with a mesh size of 8000-10000 (particle size of about 1300 nm). Selecting zinc oxide as the antimicrobial agent is advantageous in meeting the requirements for controlling the amount of metal ion precipitation.

[0095] In an embodiment of the present invention, the antimicrobial filter material is an antimicrobial filter mesh, and the molar ratio of the first metal oxide antimicrobial agent to the coating agent is (0.9-1):(0.02-0.06). Setting the amounts of the metal oxide antimicrobial agent and the coating agent within the above range allows the metal oxide antimicrobial agent and the coating agent to fully react, resulting in an antimicrobial agent with excellent antimicrobial properties while controlling costs.

[0096] In an embodiment of the present invention, the antibacterial filter material is an antibacterial filter mesh, the hydroxylation agent includes ethylene glycol, and the mass ratio of the metal oxide antibacterial agent to ethylene glycol is 1:(10-15). Ethylene glycol is rich in hydroxyl groups, and after hydrothermal treatment, the surface of the antibacterial agent is rich in hydroxyl groups. Considering that increasing the amount of ethylene glycol will correspondingly increase production costs, and that as the amount of ethylene glycol increases, the viscosity of the reaction system increases, which may limit the diffusion rate between molecules and affect the reaction efficiency, the amount of ethylene glycol is set within the above range.

[0097] In an embodiment of the present invention, the antibacterial filter material is an antibacterial filter mesh, and the volume ratio of ethylene glycol to water is (3.7-5.5):1.

[0098] In an embodiment of the present invention, the temperature of the hydrothermal reaction is 120°C to 150°C, and the time of the hydrothermal reaction is 24h to 36h. For example, the temperature of the hydrothermal reaction can be 120°C, 130°C, 140°C or 150°C, and the time of the hydrothermal reaction can be 24h, 30h or 36h. If the reaction temperature is too low, it is difficult to modify the antibacterial agent. When the reaction conditions of the hydrothermal reaction are set within the above range, the reaction can be fully reacted to obtain a modified antibacterial agent.

[0099] In an embodiment of the present invention, the antibacterial filter material is an antibacterial filter screen. The steps of providing a filter screen matrix material, mixing the filter screen matrix material with a first modified antibacterial agent, and performing smelting and extrusion into a mesh to obtain the antibacterial filter material include:

[0100] The first modified antibacterial agent is mixed with a carrier material and then extruded and granulated to obtain an antibacterial masterbatch;

[0101] A filter matrix material is provided, the filter matrix material is mixed with the antibacterial masterbatch, and the mixture is melted and extruded into a mesh to obtain an antibacterial filter material.

[0102] Since the particles of the first modified antimicrobial agent are relatively small, the particles of the first modified antimicrobial agent and the carrier material are first prepared into an antimicrobial masterbatch, and then mixed with the filter matrix raw material for processing. This method can reduce the agglomeration of the modified antimicrobial agent and make the first modified antimicrobial agent more evenly dispersed in the filter matrix.

[0103] In an embodiment of the present invention, the antimicrobial filter material is an antimicrobial filter screen, and the filter screen substrate is made of a thermoplastic. Plastics offer excellent processing properties, corrosion resistance, and chemical stability, making them suitable for extrusion. When using thermoplastics to manufacture filter screens, the antimicrobial agent can be stably loaded through physical blending or chemical grafting.

[0104] In an embodiment of the present invention, the antibacterial filter material is an antibacterial filter screen, and the carrier material comprises a thermoplastic or a degradable material; wherein the thermoplastic comprises any one of polypropylene and polyethylene, and the degradable material comprises at least one of polylactic acid, polyvinyl alcohol, a starch-based polymer, polybutylene succinate, polyhydroxyalkanoate, and polycaprolactone. The carrier material may be the same material as the filter screen substrate, or it may be a material that is different from the filter screen substrate. When both the filter screen substrate and the carrier material are thermoplastic, it is beneficial to maintain the uniformity of the filter screen.

[0105] In an embodiment of the present invention, the antimicrobial filter material is an antimicrobial filter screen, and the mass ratio of the first modified antimicrobial agent to the carrier material is 1:(4-5). Setting the amount of the first modified antimicrobial agent to the carrier material within the above range facilitates uniform dispersion of the first modified antimicrobial agent in the filter screen matrix.

[0106] In an embodiment of the present invention, the antibacterial filter material is an antibacterial filter screen, and the mass ratio of the filter screen matrix raw material to the antibacterial masterbatch is (20-30):1. Setting the amount of the filter screen matrix raw material and the antibacterial masterbatch within the above range is conducive to obtaining an antibacterial filter material with excellent antibacterial properties while controlling production costs.

[0107] In an embodiment of the present invention, in the step of providing a filter matrix raw material, mixing the filter matrix raw material with the antibacterial masterbatch, melting and extruding into a mesh to obtain an antibacterial filter material, the melting and extrusion into a mesh are carried out in a filter extruder, using conventional extrusion processes and molds.

[0108] The present invention also provides a method for preparing the antibacterial filter material, wherein the antibacterial filter material is an antibacterial carbon rod, and the method for preparing the antibacterial filter material comprises the following steps:

[0109] A carbon rod matrix raw material powder, a second modified antibacterial agent powder and a binder are provided, the carbon rod matrix raw material powder, the second modified antibacterial agent powder and the binder are mixed, and then pressed, baked and sintered to obtain an antibacterial carbon rod.

[0110] The present invention adopts a conventional preparation method to prepare an antibacterial filter. After mixing the carbon rod matrix raw material powder, the second modified antibacterial agent powder and the binder, the mixture is pressed and formed under a pressure of 1 to 5 kg and room temperature, and then baked at 80°C for 0.5h, and then sintered at 160 to 180°C for 0.5h to obtain an antibacterial carbon rod of 20*40*150 (inner diameter*outer diameter*length). Compared with conventional antibacterial carbon rods, the antibacterial carbon rod provided by the present invention uses a second modified antibacterial agent instead of a conventional antibacterial agent. Due to the positive or negative charge on the surface of the second modified antibacterial agent, it can not only reduce the agglomeration of antibacterial agent molecules through the electrostatic repulsion between molecules, making the antibacterial agent more evenly dispersed, but also enhance the interaction between the antibacterial agent and bacteria, thereby significantly improving the antibacterial effect of the antibacterial filter material.

[0111] In an embodiment of the present invention, the antibacterial filter material is an antibacterial carbon rod, and the second modified antibacterial agent powder is prepared by the following steps:

[0112] An inorganic metal salt, a coating agent, a hydroxylating agent and a complexing agent are mixed and subjected to a hydrothermal reaction to obtain a metal oxide gel. The metal oxide gel is cleaned and dried, and ground to obtain a second modified antibacterial agent powder; wherein the inorganic metal salt includes an inorganic zinc salt or an inorganic copper salt.

[0113] Hydroxylating agents are used to modify hydroxyl groups on the surface of metal oxide antimicrobial agents. After modification, the coating agent and the hydroxyl groups react to form chemical bonds, thereby connecting the coating agent to the antimicrobial agent. The addition of a chelating agent facilitates the formation of a metal oxide gel, improving the binding ability of the modified antimicrobial agent to the carrier material and enhancing the stability of the antimicrobial coating. The use of inorganic zinc salts or inorganic copper salts to prepare modified antimicrobial agents can meet the requirements for silver ion precipitation and antimicrobial performance. In one embodiment of the present invention, an inorganic zinc salt is selected to prepare the second modified antimicrobial agent, which has excellent bactericidal efficacy. Zinc ions are a trace element required by the human body, and the trace amount of zinc ions in the filtered water is beneficial to human health.

[0114] In an embodiment of the present invention, the antibacterial filter material is an antibacterial carbon rod, and the molar ratio of the inorganic metal salt to the coating agent is (0.8-1):(0.04-0.06). Too little coating agent will not produce a metal oxide gel. Setting the amounts of the metal oxide antibacterial agent and the coating agent within the above range allows the metal oxide antibacterial agent and the coating agent to fully react, resulting in an antibacterial agent with excellent antibacterial properties while also controlling costs.

[0115] In an embodiment of the present invention, the antibacterial filter material is an antibacterial carbon rod, the hydroxylating agent includes ethylene glycol, the complexing agent includes ammonia water, the mass concentration of the inorganic metal salt in the hydroxylating agent is 0.2 to 0.45 g / mL, and the volume ratio of ethylene glycol to ammonia water is (100 to 120): (3 to 6). Ethylene glycol provides hydroxyl groups for the antibacterial agent to react with the encapsulating agent through the hydroxyl groups. Setting the amount of ethylene glycol within the above range is conducive to obtaining a second modified antibacterial agent with good antibacterial properties and controlling costs. Metal oxide gel cannot be obtained without adding ammonia water, using too little ammonia water, or using too much ammonia water. Setting the amount of ammonia water within the above range can successfully produce a metal oxide gel with a smooth surface.

[0116] In an embodiment of the present invention, the antibacterial filter material is an antibacterial carbon rod, the hydrothermal reaction temperature is 120°C to 150°C, and the hydrothermal reaction time is 24 hours to 36 hours. When the hydrothermal reaction conditions are set within the above ranges, sufficient reaction can be achieved to obtain a modified antibacterial agent.

[0117] In an embodiment of the present invention, the steps of washing and drying the metal oxide gel, grinding, and obtaining a second modified antimicrobial agent powder include:

[0118] The metal oxide gel was washed with ethanol and water in sequence, dried at 100° C., and ground to obtain a second modified antibacterial agent powder.

[0119] In an embodiment of the present invention, the antibacterial filter material is an antibacterial carbon rod, and the mass ratio of the carbon rod matrix powder, the second modified antibacterial agent powder, and the binder is 100:(0.1-2):(5-12). Setting the amounts of the carbon rod matrix powder, the second modified antibacterial agent powder, and the binder within the above range can provide sufficient antibacterial performance while controlling costs.

[0120] In an embodiment of the present invention, the antibacterial filter material is an antibacterial carbon rod, the carbon rod matrix raw material powder includes porous carbon material powder, and the porous carbon material powder includes carbon powder. The technical solution of the present invention uses conventional raw materials to prepare the antibacterial carbon rod, for example, carbon powder can be used as the raw material.

[0121] In an embodiment of the present invention, the antibacterial filter material is an antibacterial carbon rod, and the particle size of the porous carbon material powder is 5-8 μm. The technical solution of the present invention uses porous carbon material powder of conventional fineness to prepare the antibacterial carbon rod, for example, porous carbon material powder with a particle size of 5-8 μm.

[0122] In an embodiment of the present invention, when the antimicrobial filter material is an antimicrobial carbon rod, the second modified antimicrobial agent powder is passed through a 30-50 mesh sieve before mixing the inorganic metal salt, encapsulating agent, hydroxylating agent, and chelating agent. The fineness of the second modified antimicrobial agent powder is controlled within the above-mentioned range to facilitate uniform mixing of the porous carbon material powder and the second modified antimicrobial agent powder.

[0123] The present invention provides a filter element comprising the antibacterial filter material described in the aforementioned technical solution, or comprising an antibacterial filter material prepared according to the method for preparing the antibacterial filter material described in the aforementioned technical solution. Because the filter element includes all technical solutions of the antibacterial filter material and thus possesses all the beneficial effects of the antibacterial filter material, the present invention will not further elaborate on each of them.

[0124] The present invention provides a water purification device, which includes the filter element. Since the water purification device includes all technical solutions of the filter element and thus has all the beneficial effects of the filter element, the present invention will not elaborate on them one by one here.

[0125] The technical solutions of the present invention are further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only used to explain the present invention and are not used to limit the present invention.

[0126] Example 1

[0127] An antibacterial filter comprises a filter matrix having a mesh structure, wherein the filter matrix is ​​provided with a modified antibacterial agent both inside and on the surface of the filter matrix; the modified antibacterial agent comprises a metal oxide antibacterial agent and an encapsulating agent connected to the metal oxide antibacterial agent via a chemical bond, wherein the surface of the encapsulating agent carries a negative charge.

[0128] The antibacterial filter is prepared by the following steps:

[0129] (1) The raw materials were weighed according to the ratio of 8.14 g nano zinc oxide (particle size of 8000 mesh) + 0.96 g citric acid ((the molar ratio of zinc oxide to citric acid is 0.1:0.005)) + 80 mL ethylene glycol + 20 mL water, and the raw materials were placed in a reactor (containing a polytetrafluoroethylene lining), kept warm at 120 ° C for 24 h for hydrothermal reaction, poured out, centrifuged with a centrifuge, poured out the supernatant, took out the solid, washed it with ethanol three times, and then washed it with pure water three times, and then placed in a vacuum oven at 100 ° C to obtain a modified antibacterial agent.

[0130] (2) 1 kg of modified antibacterial agent, 2.5 kg of polylactic acid and 2 kg of polybutylene succinate were mixed, melted and extruded, crushed and granulated to obtain antibacterial masterbatch.

[0131] (3) 1 kg of antibacterial masterbatch and 20 kg of polypropylene were added to the feed hopper of the filter extruder, melted and extruded to produce the antibacterial filter material.

[0132] The Zeta potential of the modified antibacterial agent was measured to be -28.0 mV.

[0133] Example 2

[0134] An antibacterial filter comprises a filter matrix having a mesh structure, wherein a first modified antibacterial agent is disposed inside and on the surface of the filter matrix; the first modified antibacterial agent comprises a first metal oxide antibacterial agent and an encapsulating agent connected to the first metal oxide antibacterial agent via a chemical bond, wherein the surface of the encapsulating agent carries a positive charge.

[0135] The antibacterial filter is prepared by the following steps:

[0136] (1) The raw materials were weighed according to the ratio of 8.14 g nano zinc oxide + 1.6 g hexadecyltrimethylammonium chloride (CTAC) (M = 320.986) + 80 mL ethylene glycol + 20 mL water (the molar ratio of zinc oxide to CTAC was 0.1:0.005), and the raw materials were placed in a reactor (containing a polytetrafluoroethylene lining), kept warm at 120 ° C for 24 h for hydrothermal reaction, poured out, centrifuged with a centrifuge, poured out the supernatant, took out the solid, washed it three times with ethanol, and then washed it three times with pure water, and then placed in a vacuum oven at 100 ° C for drying to obtain the first modified antibacterial agent.

[0137] (2) 1 kg of the first modified antibacterial agent, 2.5 kg of polylactic acid and 2 kg of polybutylene succinate were mixed, melted and extruded, crushed and granulated to obtain an antibacterial masterbatch.

[0138] (3) 1 kg of antibacterial masterbatch and 20 kg of polypropylene were added to the feed hopper of the filter extruder, melted and extruded to produce the antibacterial filter material.

[0139] The Zeta potential of the first modified antibacterial agent was measured to be 34.7 mV.

[0140] Example 3

[0141] Compared with Example 1, the difference is that the mass of nano zinc oxide is 7.5 g, and the mass of citric acid is 0.38 g (the molar ratio of zinc oxide to citric acid is 0.9:0.002).

[0142] The Zeta potential of the first modified antibacterial agent was measured to be -25.6 mV.

[0143] Example 4

[0144] Compared with Example 1, the difference is that the mass of citric acid is 1.15 g (the molar ratio of zinc oxide to citric acid is 0.1:0.006).

[0145] The Zeta potential of the first modified antibacterial agent was measured to be -28.5 mV.

[0146] Example 5

[0147] Compared with Example 2, the difference is that the mass of nano zinc oxide is 7.5 g (the molar ratio of zinc oxide to CTAC is 0.09:0.005).

[0148] The Zeta potential of the first modified antibacterial agent was measured to be 34.6 mV.

[0149] Example 6

[0150] Compared with Example 2, the difference is that the mass of CTAC is 0.9 g (the molar ratio of zinc oxide to CTAC is 0.1:0.003).

[0151] The Zeta potential of the first modified antibacterial agent was measured to be 30.3 mV.

[0152] Example 7

[0153] Compared with Example 2, the difference is that the amount of ethylene glycol used is 110 mL.

[0154] The Zeta potential of the first modified antibacterial agent was measured to be 34.3 mV.

[0155] Example 8

[0156] Compared with Example 2, the difference is that the amount of ethylene glycol used is 74 mL.

[0157] The Zeta potential of the first modified antibacterial agent was measured to be 34.3 mV.

[0158] Example 9

[0159] Compared with Example 2, the difference is that the temperature of the hydrothermal reaction is 150°C.

[0160] The Zeta potential of the first modified antibacterial agent was measured to be 34.6 mV.

[0161] Example 10

[0162] Compared with Example 2, the difference is that in the step of preparing the antibacterial masterbatch, 4.5 kg of polypropylene is used instead of 2.5 kg of polylactic acid + 2 kg of polybutylene succinate.

[0163] Example 11

[0164] An antibacterial carbon rod includes a filter matrix, the antibacterial filter material includes an antibacterial carbon rod, the antibacterial carbon rod includes a carbon rod matrix, the interior and surface of the carbon rod matrix are both provided with a pore structure, the interior and surface of the carbon rod matrix are both provided with a second modified antibacterial agent, and the surface of the encapsulating agent is positively charged.

[0165] The antibacterial filter stick is prepared by the following steps:

[0166] (1) 43.48 g of 3.5-hydrated zinc borate, 2.3 g of didodecyldimethylammonium bromide (DDAB), and 100 mL of ethylene glycol were mixed and stirred for 1 h. 2 mL of ammonia water was added and placed in a reactor (containing a polytetrafluoroethylene liner). The mixture was kept at 150 ° C for 24 h for hydrothermal reaction. The zinc oxide gel was taken out, washed three times with ethanol, and then washed three times with pure water. It was dried in a vacuum oven at 100 ° C for 24 h, ground, and passed through a 30-mesh sieve to obtain a second modified antibacterial agent powder.

[0167] (2) 0.1 g of the second modified antibacterial agent powder was mixed with 100 g of carbon powder and 10 g of ultra-high molecular weight polyethylene (molecular weight 6,000,000-70,000,000), and then pressed, baked, and sintered to obtain an antibacterial carbon rod (mixed, pressed, baked, and sintered at one time).

[0168] The Zeta potential of the first modified antibacterial agent was measured to be 35 mV.

[0169] Example 12

[0170] Compared with Example 11, the difference is that the mass of the second modified antibacterial agent powder is 0.5 g.

[0171] The Zeta potential of the first modified antibacterial agent was measured to be 33 mV.

[0172] Example 13

[0173] Compared with Example 11, the difference is that the mass of the second modified antibacterial agent powder is 1 g.

[0174] The Zeta potential of the first modified antibacterial agent was measured to be 35 mV.

[0175] Example 14

[0176] Compared with Example 11, the difference is that the mass of the second modified antibacterial agent powder is 5 g.

[0177] The Zeta potential of the first modified antibacterial agent was measured to be 34 mV.

[0178] Example 15

[0179] Compared with Example 11, the difference is that 43.48 g of 3.5-hydrated zinc borate is replaced by 29.75 g of hexahydrated zinc nitrate.

[0180] The Zeta potential of the modified antibacterial agent was measured to be 37 mV.

[0181] Example 16

[0182] Compared with Example 11, the difference is that the amount of ethylene glycol used is 120 mL.

[0183] The Zeta potential of the first modified antibacterial agent was measured to be 36 mV.

[0184] Example 17

[0185] Compared with Example 11, the difference is that the amount of ammonia water used is 3 mL.

[0186] The Zeta potential of the first modified antibacterial agent was measured to be 37 mV.

[0187] Example 18

[0188] An antibacterial carbon rod includes a filter matrix, the antibacterial filter material includes an antibacterial carbon rod, the antibacterial carbon rod includes a carbon rod matrix, the interior and surface of the carbon rod matrix are both provided with a pore structure, the interior and surface of the carbon rod matrix are both provided with a second modified antibacterial agent, and the surface of the encapsulating agent is negatively charged.

[0189] The antibacterial filter stick is prepared by the following steps:

[0190] (1) 43.48 g of 3.5-hydrated zinc borate, 0.77 g of citric acid, and 100 mL of ethylene glycol were mixed and stirred for 1 h. 3 mL of ammonia water was added and placed in a reactor (containing a polytetrafluoroethylene liner). The mixture was kept at 150 ° C for 24 h for hydrothermal reaction. The zinc oxide gel was taken out, washed three times with ethanol, and then washed three times with pure water. It was dried in a vacuum oven at 100 ° C for 24 h, ground, and passed through a 30-mesh sieve to obtain a second modified antibacterial agent powder.

[0191] (2) 2 g of the second modified antibacterial agent powder was mixed with 100 g of carbon powder and 10 g of ultra-high molecular weight polyethylene, and then pressed, baked, and sintered to obtain an antibacterial carbon rod (one-time mixing, one-time pressing, baking, and sintering to obtain an antibacterial carbon rod).

[0192] The Zeta potential of the first modified antibacterial agent was measured to be -26 mV.

[0193] Comparative Example 1

[0194] Compared with Example 2, the difference is that no antibacterial masterbatch is added, and only 20 kg of polypropylene is added to the filter extruder to prepare the antibacterial filter material.

[0195] Comparative Example 2

[0196] Compared with Example 2, the difference is that unmodified zinc oxide is used instead of the first modified zinc oxide in step (2) of preparing the antibacterial filter material.

[0197] Comparative Example 3

[0198] Compared with Example 2, the difference is that the mass of CTAC is 0.5 g.

[0199] The Zeta potential of the modified antibacterial agent was measured to be 6.3 mV.

[0200] Comparative Example 4

[0201] Compared with Example 2, the difference is that the mass of ethylene glycol is 20 mL.

[0202] The Zeta potential of the modified antibacterial agent was measured to be 0.67 mV.

[0203] Comparative Example 5

[0204] An antibacterial carbon rod is obtained by mixing and sintering 15g of silver-loaded carbon particles, 100g of carbon powder and 10g of ultra-high molecular weight polyethylene (the antibacterial agent is silver-loaded carbon particles, purchased from Ningbo Aiquou).

[0205] Comparative Example 6

[0206] Compared with Example 11, the second modified antibacterial agent prepared in Example 1 was used instead of the second modified antibacterial agent powder.

[0207] Comparative Example 7

[0208] Compared with Example 11, the difference is that 8g of the second modified antibacterial agent powder is mixed with 800g of carbon powder and 80g of ultra-high molecular weight polyethylene, and then pressed, baked, and sintered to cut out 8 antibacterial carbon rods of the same length as Example 11).

[0209] Performance Testing

[0210] 1. Sterilization effect test of antibacterial filter:

[0211] The 10-inch / 3m antibacterial filter screens (thickness 0.34 mm, pore size 10 mm) of Examples 1-10 and Comparative Examples 1-4 were rolled and stuffed into an empty shell filter element with a volume of 800 mL to prepare a test filter element and tested for sterilization effect. The test results are shown in Table 1.

[0212] The test method is as follows:

[0213] Test method for instantaneous sterilization rate: spike the tap water dechlorinated with activated carbon to make the concentration of E. coli spiked solution greater than 50,000 cfu / 100 mL, prepare the spiked solution, then rinse the filter element to be tested with the spiked solution for 5 minutes, control the flow rate at 1.5 L / min, and test the E. coli concentration in the effluent.

[0214] Test method for immersion sterilization rate: spike the tap water dechlorinated with activated carbon to make the concentration of E. coli spiked solution greater than 50,000 cfu / 100 mL, prepare the spiked solution, then rinse the filter element to be tested with the spiked solution for 5 minutes, control the flow rate at 1.5 L / min, soak for 8 hours, and test the E. coli concentration in the effluent.

[0215] Table 1 Bactericidal performance test results of antibacterial filters of Examples 1-10 and Comparative Examples 1-4

[0216]

[0217]

[0218] As shown in Table 1, the antibacterial filter screens of Examples 1-10 have good sterilization effects and can achieve instant sterilization (sterilization rate > 95% at a flow rate of 1.5 L / min). Compared with the sterilization rate of Comparative Examples 1-4 after immersion for 8 hours, the sterilization rate is significantly improved.

[0219] 2. Test of desalination rate and recovery rate of antibacterial filter:

[0220] The life and performance of the RO membrane element in the filter element to be tested under specific operating conditions were tested. Taking Examples 1-2, Examples 5-6, Example 10 and Comparative Examples 1-2 as examples, the test results are shown in Table 2. The test method is as follows:

[0221] Using fresh, spiked water as the inlet water, the pressure before the membrane was set at 125 psi, the recovery rate was 63-70%, and the water temperature was 25°C. A flushed pre-filter was connected before the RO membrane. The system was operated continuously to produce water. Flow rate and desalination efficiency were tested at 1 / 4, 2 / 4, 3 / 4, and 4 / 4 of the total water production volume.

[0222] Table 2 Performance test results of filter screen in membrane element

[0223]

[0224]

[0225] As can be seen from Table 2, the antibacterial filter prepared by the present invention has little effect on water flux and desalination rate.

[0226] 3. Odor test after using the antibacterial filter:

[0227] The antibacterial filters of Examples 1-10 and Comparative Examples 1-4 were tested for odor as follows: activated carbon-dechlorinated tap water was spiked to a concentration of E. coli greater than 50,000 cfu / 100 mL. A spiked solution was prepared and the filter element to be tested was rinsed with the spiked solution for 5 minutes. The solution was then allowed to stand for one week to observe for the presence of odor. The test results are shown in Table 3.

[0228] Table 3 Odor test results of the antibacterial filter screens of Examples 1-10 and Comparative Examples 1-4

[0229]

[0230]

[0231] As can be seen from Table 3, the antibacterial filter prepared in the embodiment of the present invention has no odor after being rinsed and soaked in water for one week, while the antibacterial filter prepared in the comparative example has odor.

[0232] 4. Test of the sterilization effect of antibacterial carbon rods:

[0233] The antibacterial carbon rods of Examples 11-18 and Comparative Examples 5-7 were encapsulated into 500 mL empty shell filter cartridges to prepare test filter cartridges and tested for bactericidal efficacy. The test results are shown in Table 4. For Comparative Example 7, four carbon rods prepared were tested for antibacterial performance, designated Comparative Example 7-1, Comparative Example 7-2, Comparative Example 7-3, and Comparative Example 7-4, respectively.

[0234] The test method is as follows:

[0235] Test method for instantaneous sterilization rate: spike the tap water dechlorinated with activated carbon to make the concentration of E. coli spiked solution greater than 100,000 cfu / 100 mL, prepare the spiked solution, then rinse the filter element to be tested with the spiked solution for 5 minutes, control the flow rate at 1.5 L / min, and test the E. coli concentration in the effluent.

[0236] Test method for immersion sterilization rate: Add spiked activated carbon dechlorinated tap water to a concentration of E. coli greater than 100,000 cfu / 100 mL to prepare a spiked solution. The filter element to be tested is then rinsed with the spiked solution for 5 minutes at a flow rate of 1.5 L / min. After soaking for 8 hours, the E. coli concentration in the effluent is tested.

[0237] Testing method for zinc ion precipitation: Take 1L of water sample after water discharge and count the amount of zinc ion precipitation.

[0238] Table 4 Bactericidal performance test results of the filter screens of Examples 11-18 and Comparative Examples 5-7

[0239]

[0240]

[0241] The following conclusions can be drawn from Table 4:

[0242] (1) The antibacterial carbon rods of Examples 11-18 have good bactericidal effects and can achieve instantaneous sterilization (sterilization rate > 99% at a flow rate of 1.5 L / min). Compared with the sterilization rate of Comparative Example 5, which was soaked for 8 hours, the sterilization rate was significantly improved.

[0243] (2) The increase in zinc ion precipitation of the antibacterial carbon rods of Examples 11-18 can reach below 0.2 mg / L, which meets the health and safety standards.

[0244] (3) From the test data of Example 11 and Comparative Example 6, it can be seen that the antibacterial effect of Comparative Example 6 is deteriorated. This is because the fineness of the antibacterial agent powder and the carbon powder does not match, making it difficult to mix them. The antibacterial agent will settle to the bottom and have almost no antibacterial effect.

[0245] (4) It can be seen from the test data of Example 11 and Comparative Example 7 that compared with the carbon rods produced by the one-time mixing, one-time pressing, baking and sintering method, the antibacterial effect and antibacterial stability of the carbon rods obtained by mixing large quantities of raw materials and then cutting multiple carbon rods (the one-out-of-8 method) are worse. This may be because the distribution of the antibacterial agent in the one-out-of-8 method will show large differences, and it is difficult to achieve a very uniform mixing, which leads to a worse antibacterial effect.

[0246] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformation made by utilizing the contents of the present invention specification under the technical concept of the present invention, or any direct / indirect application in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. An antibacterial filter material, characterized in that: A filter element for a water purification device, wherein the antibacterial filter material comprises an antibacterial filter screen, the antibacterial filter screen comprises a filter screen matrix, the filter screen matrix forms a mesh structure, and a first modified antibacterial agent is provided inside and on the surface of the filter screen matrix; The first modified antibacterial agent includes a first metal oxide antibacterial agent and an encapsulating agent connected to the first metal oxide antibacterial agent through a chemical bond, and the surface of the encapsulating agent has a positive charge or a negative charge.

2. The antibacterial filter material according to claim 1, wherein The antibacterial filter material is an antibacterial filter mesh: The surface of the encapsulating agent is positively charged, and the Zeta potential of the first modified antimicrobial agent is 30mV to 35mV; and / or, The surface of the encapsulating agent is negatively charged, and the Zeta potential of the first modified antimicrobial agent is -25mV to -30mV; and / or, The surface of the encapsulating agent is positively charged, and the encapsulating agent comprises a cationic organic compound; and / or, The surface of the encapsulating agent is negatively charged, and the encapsulating agent comprises carboxylic acid and its derivatives.

3. The antibacterial filter material according to claim 2, wherein The antibacterial filter material is an antibacterial filter mesh: The surface of the encapsulating agent is positively charged, and the encapsulating agent comprises a quaternary ammonium salt; wherein the quaternary ammonium salt comprises at least one of tetramethylammonium bromide, dodecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, behenyltrimethylammonium bromide, dihexadecyldimethylammonium bromide, ditetradecyldimethylammonium bromide and dioctadecyldimethylammonium bromide; and / or, The surface of the encapsulating agent is negatively charged, and the encapsulating agent comprises citric acid.

4. An antibacterial filter material, characterized in that: A filter element for a water purification device, wherein the antibacterial filter material comprises an antibacterial carbon rod, the antibacterial carbon rod comprises a carbon rod matrix, the interior and surface of the carbon rod matrix are provided with a pore structure, and the interior and surface of the carbon rod matrix are provided with a second modified antibacterial agent; The second modified antibacterial agent includes a second metal oxide antibacterial agent and an encapsulating agent connected to the second metal oxide antibacterial agent through a chemical bond, and the surface of the encapsulating agent has a positive charge or a negative charge.

5. The antibacterial filter material according to claim 4, wherein The antibacterial filter material is an antibacterial carbon rod: The surface of the encapsulating agent is positively charged, and the Zeta potential of the second modified antimicrobial agent is 30mV to 37mV; and / or, The surface of the encapsulating agent is negatively charged, and the Zeta potential of the modified antibacterial agent is -21mV to -26mV; and / or, The surface of the encapsulating agent is positively charged, and the encapsulating agent comprises a cationic organic compound; and / or, The surface of the encapsulating agent is negatively charged, and the encapsulating agent comprises carboxylic acid and its derivatives.

6. The antibacterial filter material according to claim 5, wherein The antibacterial filter material is an antibacterial carbon rod: The surface of the encapsulating agent is positively charged, and the cationic organic compound includes a quaternary ammonium salt; wherein the quaternary ammonium salt includes at least one of tetramethylammonium bromide, dodecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, behenyltrimethylammonium bromide, dihexadecyldimethylammonium bromide, ditetradecyldimethylammonium bromide and dioctadecyldimethylammonium bromide; and / or, The surface of the encapsulating agent is negatively charged, and the encapsulating agent comprises citric acid.

7. A method for preparing an antibacterial filter material according to any one of claims 1 to 3, characterized in that: The antibacterial filter material is an antibacterial filter mesh, and the preparation method of the antibacterial filter material comprises the following steps: A filter matrix material is provided, the filter matrix material is mixed with a first modified antibacterial agent, and then smelted and extruded into a mesh to obtain an antibacterial filter material.

8. The method for preparing the antibacterial filter material according to claim 7, wherein: The antibacterial filter material is an antibacterial filter mesh, and the first modified antibacterial agent is prepared by the following steps: The first metal oxide antibacterial agent, the encapsulating agent, the hydroxylation agent and water are mixed and subjected to a hydrothermal reaction to obtain a first modified antibacterial agent.

9. The method for preparing the antibacterial filter material according to claim 8, wherein: The antibacterial filter material is an antibacterial filter mesh: The first metal oxide antibacterial agent includes at least one of zinc oxide and copper oxide; and / or, The molar ratio of the first metal oxide antibacterial agent to the encapsulating agent is (0.9-1): (0.02-0.06); and / or, The hydroxylation agent includes ethylene glycol, and the mass ratio of the metal oxide antibacterial agent to the ethylene glycol is 1: (10-15).

10. The method for preparing the antibacterial filter material according to claim 7, wherein: The antibacterial filter material is an antibacterial filter screen. The steps of providing a filter screen matrix material, mixing the filter screen matrix material with a first modified antibacterial agent, and performing smelting and extruding into a mesh to obtain the antibacterial filter material include: The first modified antibacterial agent is mixed with a carrier material and then extruded and granulated to obtain an antibacterial masterbatch; A filter matrix material is provided, the filter matrix material is mixed with the antibacterial masterbatch, and the mixture is melted and extruded into a mesh to obtain an antibacterial filter material.

11. The method for preparing the antibacterial filter material according to claim 10, wherein: The antibacterial filter material is an antibacterial filter mesh: The filter screen substrate is made of thermoplastic plastic, wherein the thermoplastic plastic includes any one of polypropylene and polyethylene; and / or, The carrier material comprises a thermoplastic or a degradable material; wherein the degradable material comprises at least one of polylactic acid, polyvinyl alcohol, starch-based polymer, polybutylene succinate, polyhydroxyalkanoate and polycaprolactone; and / or, The mass ratio of the first modified antimicrobial agent to the carrier material is 1:(4-5); and / or, The mass ratio of the filter matrix raw material to the antibacterial masterbatch is (20-30):

1.

12. A method for preparing the antibacterial filter material according to any one of claims 4 to 6, characterized in that: The antibacterial filter material is an antibacterial carbon rod, and the preparation method of the antibacterial filter material comprises the following steps: A carbon rod matrix raw material powder, a second modified antibacterial agent powder and a binder are provided, the carbon rod matrix raw material powder, the second modified antibacterial agent powder and the binder are mixed, and then pressed, baked and sintered to obtain an antibacterial carbon rod.

13. The method for preparing the antibacterial filter material according to claim 12, wherein: The antibacterial filter material is an antibacterial carbon rod, and the second modified antibacterial agent powder is prepared by the following steps: An inorganic metal salt, a coating agent, a hydroxylating agent and a complexing agent are mixed and subjected to a hydrothermal reaction to obtain a metal oxide gel. The metal oxide gel is cleaned and dried, and ground to obtain a second modified antibacterial agent powder; wherein the inorganic metal salt includes an inorganic zinc salt or an inorganic copper salt.

14. The method for preparing the antibacterial filter material according to claim 13, wherein: The antibacterial filter material is an antibacterial carbon rod: The molar ratio of the inorganic metal salt to the encapsulating agent is (0.8-1): (0.04-0.06); and / or, The hydroxylation agent includes ethylene glycol, the complexing agent includes ammonia water, the mass concentration of the inorganic metal salt in the hydroxylation agent is 0.2-0.45 g / mL, and the volume ratio of the ethylene glycol to the ammonia water is (100-120): (3-6).

15. The method for preparing the antibacterial filter material according to claim 12, wherein: The antibacterial filter material is an antibacterial carbon rod: The mass ratio of the carbon rod matrix raw material powder, the second modified antibacterial agent powder and the binder is 100: (0.1-2): (5-12); and / or, Before mixing the inorganic metal salt, the encapsulating agent, the hydroxylation agent and the complexing agent, the second modified antibacterial agent powder is passed through a 30-50 mesh sieve.

16. A filter element, characterized in that: The antibacterial filter material comprises the antibacterial filter material according to any one of claims 1 to 6, or the antibacterial filter material prepared by the preparation method of the antibacterial filter material according to any one of claims 7 to 15.

17. A water purification device, characterized in that: Including the filter element according to claim 16.

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