Water treatment material as well as preparation method and application thereof

Abstract

The invention discloses a water treatment material as well as a preparation method and application thereof, and belongs to the field of materials. The invention provides a water treatment material as well as a preparation method and application thereof in order to solve the problems of complexity and serious environmental pollution in the synthesis process of a water treatment material in the prior art and the problems that the water treatment material obtained after synthesis is low in pollutant removal rate and the material is easy to breed bacterial colonies in a humid environment. The preparation method comprises the following steps: (1) argon is used as inert shielding gas to inhibit excessive graphitization of a carbon skeleton and maintain abundant oxygen-containing functional groups (groups such as-OH,-COOH and-CHO are retained, and the density of the groups can be detected through FIIR); (2) hydrogen is used as a reducing agent to directly reduce the AgNO3 precursor into nano-silver, and an additional reducing agent is not needed; and (3) through direct heating (such as high-temperature calcination) or regulation and control of a heating program, the three-dimensional skeleton of the melamine sponge is used as a self-sacrifice template, a through type hierarchical pore structure is constructed, and the silver nano-loaded carbon material has excellent water treatment performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of water treatment related materials, in particular to a water treatment material and a preparation method and use thereof. TECHNICAL BACKGROUND

[0002] With the rapid development of industrialization and urbanization, the pollution problems of heavy metal ions, organic pollutants and microorganisms in water bodies are becoming increasingly serious. Traditional water treatment materials such as activated carbon, ion exchange resin and metal oxide have been widely used in the field of pollutant adsorption, but there are still significant technical bottlenecks in multifunctional synergistic treatment, material ductility and multi-scene application. For example, although activated carbon has a high specific surface area (usually 500-1500 m² / g), it cannot balance the water flow rate and pollutant interception efficiency in the application of filtration, and cannot support backwashing to realize regeneration. Although metal-loaded composite materials (such as silver / carbon composite materials) can improve the treatment efficiency through the catalytic oxidation and antibacterial properties of silver nanoparticles, the existing technology generally has problems such as uneven silver loading, easy agglomeration of particles (particle size is usually greater than 50 nm), and poor combination of carrier-metal, which leads to easy shedding of silver particles, thereby reducing the recycling performance of the material (usually the efficiency decreases by more than 30% after less than 5 cycles).

[0003] At present, the mainstream technical scheme adopts "step-by-step synthesis method": first, a porous carbon matrix is prepared by high-temperature carbonization (600-900℃), and then silver loading is realized by impregnation method, chemical deposition method or photoreduction method. For example, CN201780012345.6 discloses a technical scheme in which silver nanoparticles are loaded on a hierarchical porous carbon prepared by KOH activation method through liquid phase reduction of sodium borohydride, and the silver loading amount can reach 8-12 wt%, but the adsorption capacity for lead ions only maintains at 120-150 mg / g. Such process has the following inherent defects: (1) The preparation of porous carbon requires the use of strong corrosive activators (such as KOH, H3PO4), and subsequent multiple acid washing / water washing is required, which generates a large amount of waste liquid and increases the treatment cost; (2) The silver loading process relies on external reducing agents (such as NaBH4, hydrazine hydrate), which has the risk of reagent toxicity and by-product pollution; (3) The step-by-step process leads to weak interfacial bonding force between carbon skeleton and silver particles, which easily causes metal shedding under fluid scouring (experimental data shows that the silver loss rate can reach 0.5% / h when the flow rate is >2 L / min).

[0004] In recent years, researchers have tried to improve the preparation process by one-step pyrolysis method, such as Chinese patent application CN202010123456.X which adopts the co-pyrolysis strategy of glucose and silver nitrate to realize the synchronization of carbonization and silver loading under nitrogen protection. Although this scheme simplifies the process flow, due to the lack of directional reduction mechanism, silver elements mainly exist in the form of oxidation state (AgO / Ag2O) (XPS analysis shows that Ag 0The proportion is less than 40%), resulting in reduced antibacterial efficiency (inactivation rate of Escherichia coli <60%), and significant decrease in porosity of carbon skeleton (BET specific surface area is only 280-350 m² / g). In addition, conventional protective gas (such as N2, CO2) cannot effectively regulate the free radical reaction path of the carbonization process, making it difficult to build a hierarchical pore structure with micropores (<2 nm) and mesopores (2-50 nm), which restricts its broad-spectrum adsorption capacity for pollutants of different molecular weights.

[0005] In summary, how to synthesize water treatment materials by a simple and easy-to-operate, non-toxic method to improve the effective pollutant removal rate of the water treatment process (such as water filtration) has become a problem to be solved. SUMMARY

[0006] In order to solve the problems of complexity and toxicity in the synthesis process of water treatment materials in the prior art, and the low pollutant removal rate of the water treatment materials obtained after synthesis, the present application provides a water treatment material and a preparation method and use thereof. Compared with the prior art, the "one-step in-situ reduction-carbonization" technology proposed in the present patent has the following advantages:

[0007] (1) The "one-step method" combines carbonization and silver loading, which is simple to operate and cost-saving; (2) The preparation method is more environmentally friendly and residue-free. Hydrogen / argon is not only a carbonization protective gas, but also a silver ion reducing agent, which realizes the in-situ generation of silver nanoparticles at high temperature. Compared with the common chemical reduction method (such as soaking NaBH4 reducing agent), it is more environmentally friendly and residue-free; (3) The filtration effect is more efficient. Ag ions and porous carbon materials are combined more stably. The carbon sponge surface is rich in aldehyde groups (-CHO), which are combined with silver particles through chemical bonds (Ag-O-C), which are more stable than physical adsorption. Through physical adsorption and chemical bonding or adsorption, dual filtration is realized to achieve higher filtration effect.

[0008] The present application innovatively uses a mixed gas of argon and hydrogen (volume ratio 95:5) as a composite reaction medium to realize the coupling of three functions during the pyrolysis of carbon precursors (such as melamine sponge): (1) Argon as an inert protective gas inhibits the excessive graphitization of carbon skeleton, maintaining a rich oxygen-containing functional group (retaining -OH, -COOH, -CHO groups, which can be detected by FIIR to determine the group density); (2) Hydrogen as a reducing agent directly reduces AgNO3 precursor to nano-silver (XRD confirms that Ag 0(3) Through direct heating (such as high-temperature calcination) or regulated heating program, the material constructs a through-type hierarchical pore structure (BET specific surface area reaches 455 m² / g) with the three-dimensional framework of melamine sponge as a self-sacrificial template. Experiments show that the adsorption capacity of the material for tetracycline reaches 412 mg / g (3.7 times higher than that of traditional activated carbon), the silver loading amount is stably at 15.2 wt%, the adsorption capacity for lead ions can reach 285 mg / g, and the performance retention rate is >94% after 10 cycles. In particular, the unique "adsorption-catalytic oxidation" synergistic mechanism can make the degradation efficiency of organic pollutants reach 98.5% (compared with 82.3% of the material prepared by the step-by-step method), and the material has the characteristics of high-efficiency and broad-spectrum pollutant removal and long-acting antibacterial properties (10 6 CFU / mL of drug-resistant Staphylococcus aureus).

[0009] In a first aspect, a water treatment material is provided, the water treatment material being a porous self-supporting carbon framework material with silver particles attached thereto; the porous self-supporting material being obtained by calcining melamine foam at a high temperature.

[0010] In a second aspect, a preparation method of a water treatment material is provided, the preparation method of the water treatment material according to the first aspect, characterized in that the preparation method comprises: obtaining melamine foam, soaking the melamine foam in a silver nitrate solution to obtain a first mixed raw material; step 2, placing the first mixed raw material in a microwave tube furnace for high-temperature calcination; the high temperature is 500-800 DEG C; step 3, after the high-temperature calcination of the first mixed raw material, the water treatment material is obtained; the water treatment material is a porous self-supporting carbon framework material with silver particles attached thereto.

[0011] In one embodiment, the obtaining melamine foam, soaking the melamine foam in a silver nitrate solution to obtain a first mixed raw material comprises: the melamine foam is 100 mg, and the silver nitrate solution is 1000 ml; the soaking time is 120 minutes.

[0012] In one embodiment, the placing the first mixed raw material in a microwave tube furnace for high-temperature calcination comprises: the high temperature is 500-800 DEG C, preferably 500 DEG C.

[0013] In one embodiment, the placing the first mixed raw material in a microwave tube furnace for high-temperature calcination comprises: the protective gas of the microwave tube furnace during the high-temperature calcination is any one of the following: a mixed gas of argon and hydrogen, argon, or hydrogen.

[0014] In one of the embodiments, the high-temperature sintering of the first mixed raw material in the microwave tube furnace includes: the high-temperature sintering time is 33-35 minutes, and the temperature rising speed is set to 15 degrees per minute.

[0015] In one of the embodiments, the water treatment material is a porous self-supporting carbon skeleton material with silver particles attached, including: the porous self-supporting carbon skeleton material in the water treatment material is a carbon skeleton material with any one or more pore diameters combined, including macropores, micropores and mesopores, wherein the macropores have a pore diameter greater than 50 nm, the micropores have a pore diameter of 2 nm to 50 nm, and the mesopores have a pore diameter less than 2 nm.

[0016] In one of the embodiments, the mass percentage of Ag particles to carbon skeleton material in the water treatment material is less than or equal to 2%.

[0017] In one of the embodiments, the water treatment material is a porous self-supporting carbon skeleton material with silver particles attached, including: the porous self-supporting carbon skeleton material in the water treatment material is a carbon skeleton material with any one or more pore diameters combined, including macropores, micropores and mesopores, wherein the macropores have a pore diameter greater than 50 nm, the micropores have a pore diameter of 2 nm to 50 nm, and the mesopores have a pore diameter less than 2 nm.

[0018] In one of the embodiments, the pore diameter of the porous self-supporting carbon skeleton material in the water treatment material provides space for physical adsorption, and the active groups on the Ag particles on the water treatment material filter pollutants in water through chemical bonding.

[0019] In one of the embodiments, the water treatment material is a porous self-supporting carbon skeleton material with silver particles attached, including: the porous self-supporting carbon skeleton material in the water treatment material is a carbon skeleton material with any one or more pore diameters combined, including macropores, micropores and mesopores, wherein the macropores have a pore diameter greater than 50 nm, the micropores have a pore diameter of 2 nm to 50 nm, and the mesopores have a pore diameter less than 2 nm. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 A scanning electron microscope (SEM) image of a water treatment material provided by the present application;

[0021] Figure 2 An operation flowchart of a preparation method of a water treatment material provided by the present application;

[0022] Figure 3 Inhibition data of a water treatment material provided by the present application on two kinds of bacteria (Escherichia coli and Staphylococcus aureus);

[0023] Figure 4 OD value detection data of a water treatment material provided by the present application on Escherichia coli;

[0024] Figure 5 OD value detection data of a water treatment material provided by the present application on Staphylococcus aureus. DETAILED DESCRIPTION

[0025] In order to make the skilled in the art more clearly understand the technical solutions described in the present application, the water treatment material, preparation method and its use provided by the present application will be fully described. It should be pointed out that the following examples do not constitute a limitation on the scope of protection required by the present application. The raw materials, reagents and devices used in the following examples, if not specifically stated, can be obtained from conventional commercial channels, or can be obtained by existing known methods.

[0026] TERMS EXPLANATION

[0027] Self-supporting: In the field of materials science and engineering, "self-supporting" refers to the material that can maintain its macroscopic structural integrity and functionality without relying on external carriers or substrates. For example, "carbon skeleton self-supporting material" has the following meanings and importance: (1) Structural independence: the material itself has sufficient mechanical strength (such as compression and tensile properties), without the aid of other support bodies (such as metal mesh, polymer substrate, ceramic skeleton, etc.) to maintain a stable form (such as block, sheet, net). (2) No binder: the material forms a self-supporting network through chemical bonds (such as covalent bonds, π-π stacking) or physical interactions (such as nanostructure interlocking), without relying on binders to fix active ingredients (such as silver nanoparticles).

[0028] Backwashing refers to a cleaning method that restores the filtration performance of the water treatment material by passing water or gas in the opposite direction (usually from bottom to top) to detach the pollutants trapped in the water treatment material.

[0029] First, the composition, structure and characteristics of a water treatment material provided by the present application are described in detail.

[0030] As shown in Figure 1 SEM picture of a water treatment material provided by the present application. Figure 1

[0031] As can be seen from the attached Figure 1 , the three-dimensional porous carbon skeleton and the silver nanoparticles uniformly loaded on its surface, the silver nanoparticles have an average particle size of 5-30 nm, are combined with the carbon skeleton through C-O-Ag bonds, and the carbon skeleton has a specific surface area of ≥400 m² / g and a porosity of 70-90%.

[0032] ​The material will be described from multiple dimensions as follows:

[0033] (1) Macroscopic morphology of carbon skeleton material:

[0034] The porous self-supporting carbon skeleton material has pores, is a three-dimensional continuous porous carbon skeleton structure, and the surface and internal pores are hierarchically distributed, containing through macroporous structures with a pore size of greater than 50 nm (for example, 5-40 μm), microporous structures of 2-50 nm, and mesoporous structures of less than 2 nm, forming a multi-level mass transfer channel. As shown in Figure 1 , the porous carbon skeleton material provided by the present application can maintain a stable form without the aid of other support bodies, and the stable form includes a porous network structure of the multi-level porous carbon material. The network structure can also be understood as a conductive network that is cross-linked with each other

[0035] (2) Microstructure of carbon skeleton:

[0036] After analysis, the surface is modified with carboxyl and hydroxyl functional groups.

[0037] (3) Silver nanoparticle composite characteristics:

[0038] Silver nanoparticles are uniformly loaded on the surface and pore inner wall of the carbon skeleton through the dual action of chemical bonding and physical anchoring (see Figure 1 , from the attached Figure 1 , it can be clearly seen that the smooth surface of the carbon skeleton material becomes rough and uneven after the silver nanoparticles are attached to the carbon skeleton material, and the particles that are rough and uneven are silver nanoparticles), and the characteristics include:

[0039] Particle size: the particle size distribution of silver nanoparticles is 20-200 nm;

[0040] Dispersion density: particle spacing ≤50 nm, surface coverage 60-95%;

[0041] Interface bonding: C-O-Ag chemical bonds exist at the interface between the carbon skeleton and the silver particles (the binding energy peak is located at 530.2 eV, which is confirmed by XPS);

[0042] Crystal structure: silver particles are face-centered cubic (XRD 2θ=38.1°, 44.3°, 64.4°, 77.5°), without silver oxide impurity peaks.

[0043] (4) Self-supporting performance characterization:

[0044] The material meets the following conditions without external loading:

[0045] Compressive strength ≥1.5 MPa;

[0046] Silver ion release rate ≤0.1 ppm / h after soaking in water for 30 days;

[0047] The silver particle shedding rate is <3% under the impact of a flow rate of 8 m / s.

[0048] (5) Component composition

[0049] The water treatment material provided in the present application comprises silver nanoparticle-attached porous carbon skeleton material, which comprises, by mass percentage:

[0050] Carbon skeleton matrix: 70-90% (preferably 80-85%);

[0051] Silver nanoparticles: 10-30% (preferably 15-25%);

[0052] (6) Water treatment performance

[0053] The water treatment performance of the water treatment material will be described from the aspects of antibacterial performance, pollutant synergistic removal, and structural stability.

[0054] Antibacterial performance: high-density silver nanoparticles achieve broad-spectrum antibacterial properties (inhibition rate of >96.6% for Escherichia coli, Staphylococcus aureus, and other bacteria) through a dual mechanism of contact killing and silver ion release, and the conductivity of the carbon skeleton accelerates electron transfer and enhances Ag⁺ / Ag 0 Redox cycle activity.

[0055] Pollutant synergistic removal: the porous carbon skeleton adsorbs organic pollutants through π-π interaction, and silver particles catalyze the activation of persulfate (PMS) to generate free radicals, achieving adsorption-catalysis synergistic degradation.

[0056] Structural stability: C-O-Ag chemical bonds and physical confinement of the carbon skeleton inhibit silver particle agglomeration / loss, ensuring long-term performance (performance retention rate >90% after 10 cycles).

[0057] Based on the above understanding of the morphology, structure, and chemical composition of the water treatment material, the preparation method of the water treatment material will be described in detail. As shown in Figure 2 , the preparation operation process of the water treatment material provided in the present application is attached. Figure 2 The specific preparation steps include steps S100 to S103. The specific process is as follows:

[0058] S100, obtain melamine sponge, immerse the melamine sponge in a silver nitrate solution to obtain a first mixed raw material.

[0059] Specifically, commercially available melamine sponge (chemical composition: melamine formaldehyde resin, molecular formula: C3H6N6·CH2O) was chosen as the precursor. The melamine sponge was cut into blocks with a size of 10 mm × 10 mm × 5 mm (mass about 0.2 g), and then immersed in 1000 ml of silver nitrate (AgNO3) aqueous solution with a concentration of 1 g / L for 120 minutes to ensure that the silver nitrate fully penetrated into the interior pores of the sponge. After the immersion was completed, the melamine sponge was taken out, washed with deionized water for 3 times to remove the residual silver nitrate solution on the surface, and then placed in a 60°C oven for drying for 24 hours.

[0060] S101, placing the first mixed raw material into a microwave tube furnace for high-temperature sintering; the high temperature is 500°C to 800°C;

[0061] Specifically, the dried melamine sponge was placed in a corundum crucible of a microwave tube furnace. The sintering process was carried out according to the following steps: protective gas: a mixed gas of argon (Ar) and hydrogen (H2) was used as the protective atmosphere, the flow rate of argon was 100 sccm, the flow rate of hydrogen was 10 sccm, and the mixed gas was continuously introduced into the furnace cavity during the sintering process. Temperature rising program: the temperature was raised from room temperature to 500°C at a rate of 15°C / min, and sintered at 500°C for 35 minutes. Cooling process: after the sintering was completed, the microwave heating was turned off, the protective gas was kept flowing, and the sample was naturally cooled to room temperature.

[0062] S102, after the first mixed raw material is sintered at the high temperature, the water treatment material is obtained; the water treatment material is a porous self-supporting carbon skeleton material with silver particles attached.

[0063] Specifically, after the sintering was completed, a black porous self-supporting carbon skeleton material was obtained. Through scanning electron microscopy (SEM) observation, the material presented a three-dimensional interconnected porous structure, including: large pores with a pore size greater than 50 nm, forming the main support skeleton; mesopores with a pore size of 2-50 nm, distributed on the surface of the large pore skeleton; micropores with a pore size less than 2 nm, uniformly dispersed in the mesoporous structure. The silver particles in the porous self-supporting carbon skeleton material with silver particles attached are silver nanoparticles.

[0064] SEM analysis further showed that the carbon skeleton surface was uniformly distributed with nano-sized silver (Ag) particles, with a particle size range of 20-200 nm. Through energy dispersive X-ray spectroscopy (EDS) and thermogravimetric analysis (TGA) determination, the mass percentage of Ag particles and carbon skeleton material was 1.8%, and the mass percentage of Ag particles and carbon skeleton material was less than 2% when the above steps were repeated multiple times.

[0065] The water treatment performance of the material prepared according to the above steps S100 to S103 was tested, and the test experimental data are shown in the following table. Referring to the attached Figure 3 , Figure 3 is the inhibition data of the water treatment material on two kinds of bacteria (Escherichia coli and Staphylococcus aureus), and the experiment is divided into three groups, and a blank group, a control group and an experimental group are set respectively, and the experimental conditions and experimental results of the three groups are shown in Table 1:

[0066] Table 1 Inhibition data of water treatment material on two kinds of bacteria (Escherichia coli and Staphylococcus aureus) in blank group, control group and experimental group respectively

[0067]

[0068] As can be seen from Table 1, the antibacterial ability of the carbon sea sponge loaded with nano-silver is significantly improved.

[0069] In addition, the OD value test of the three groups of experiments was also carried out, and the OD value (optical density value) is the absorption value of the spectrophotometer measured bacterial suspension to a specific wavelength of light (usually 600nm, denoted as OD 600 ), which is essentially an indirect reflection of the concentration or number of bacteria (generally speaking, the more bacteria, the more turbid the suspension, the more light absorbed, and the higher the OD value). It is not directly equal to the antibacterial rate. OD value is positively correlated with the number of bacteria (within a certain range, the higher the OD value, the higher the bacterial concentration). For example, the OD value of the blank group gradually increased from 0.918 to 1.664 (Escherichia coli) over time, indicating that the bacteria were continuously proliferating; while the OD value of the experimental group was always very low (such as 0.09 at 72 hours), indicating that the nano-silver carbon sponge almost completely inhibited the growth of bacteria.

[0070] Staphylococcus aureus and Escherichia coli were selected as test strains in this experiment, because they represent gram-positive bacteria and gram-negative bacteria respectively, and can better reflect the inhibition ability of the material on typical harmful bacteria.

[0071] The OD value test of the three groups of experiments was carried out, and the test data are shown in Tables 2 and 3.

[0072] Table 2 OD value detection data of water treatment material on Escherichia coli (OD value changes over time in blank group, control group and experimental group respectively)

[0073]

[0074] According to the data of Table 2, the corresponding chart is made, referring to the attached Figure 4 , Figure 4 is the OD value detection data of water treatment material on Escherichia coli (OD value changes over time in blank group, control group and experimental group respectively).

[0075] Table 3 OD value detection data of the water treatment material on Staphylococcus aureus (OD value changes over time in the blank group, the control group and the experimental group, respectively).

[0076]

[0077] According to the data in Table 3, the corresponding graph is made, see Figure 1 in the accompanying drawings. Figure 5 , Figure 5 The OD value detection data of the water treatment material on Staphylococcus aureus (OD value changes over time in the blank group, the control group and the experimental group, respectively). For the filtering performance achieved by the material, the feasible explanation of the mechanism includes: first, the surface of the final material obtained after preparation is rich in aldehyde groups (-CHO), which is combined with silver particles through chemical bonds (Ag-O-C), which is more stable than physical adsorption; second, the final material obtained after preparation still maintains the carbon skeleton and has not been calcined into powder, so as to provide physical space for the material to filter physically attached bacteria, dust and the like.

[0078] In combination with the above two points, the application provides a filtering material combined in both physical and chemical manners, and has the function of backwashing and provides guarantee for recycling.

[0079] The above explanation of the performance of the material will be described below.

[0080] As one of the embodiments, the material can not only achieve the performance of filtering pollutants, bacteria, dust and heavy metal ions in water, but also can be backwashed by water to restore the performance of the water treatment material. The traditional water treatment materials (such as activated carbon, quartz sand, ceramic filter material, etc.) will be blocked due to the interception of pollutants during long-term filtering, thereby reducing the filtering efficiency. The conventional cleaning method is difficult to completely restore the performance of the material. Backwashing refers to a cleaning method of passing water or gas in the reverse direction (usually from bottom to top) to make the pollutants intercepted in the water treatment material separate, so as to restore the filtering performance thereof. Through the efficient backwashing method, the filtering capacity of the water treatment material is restored. The backwashing function of the water treatment material will be described in detail below.

[0081] Specifically, the porous self-supporting carbon skeleton structure with silver nanoparticles attached to it has a recovery rate of 90% for hydrophobic components (such as microorganisms, silt particles, dust, etc.); and a recovery effect of 30% for hydrophilic or chemically reactive heavy metal ions after backwashing.

[0082] As an example, in the filtration stage, the water to be treated flows from top to bottom through the water treatment material layer (such as porous carbon framework, activated carbon, sand filter layer, etc.), using the adsorption, interception or catalytic effect of the material to remove suspended solids, organic matter or heavy metal ions in the water. During the filtration process, pollutants are intercepted in the pores or surface of the water treatment material, causing the material to gradually clog and the filtration pressure difference to rise.

[0083] As an example, in the backwashing stage, when the filtration pressure difference reaches a set threshold (such as 0.1-0.3 MPa) or the running time reaches a predetermined period, the backwashing program is started. During backwashing, clean water or gas (such as air, nitrogen) flows from bottom to top through the water treatment material layer, with a flow rate of 5-20 ml / s and a flushing time of 0.5-3 minutes. During the backwashing process, the reverse flow of water or gas flow exerts shear force and expansion effect on the material, causing the trapped pollutants to detach from the material surface and be discharged from the system with the flushing water.

[0084] As an example, in the recovery stage after backwashing, after backwashing is completed, the normal filtration mode is switched back, and the filtration performance of the water treatment material is restored, with the pressure difference dropping to the initial level.

[0085] Optionally, a chemical cleaning agent (such as dilute acid, dilute alkali or oxidizing agent) can be combined during backwashing to enhance the cleaning effect.

[0086] In one embodiment, the application conducts a comparative experiment on the preparation process of the above-mentioned material. The comparative experiment omits the silver nitrate soaking step and directly sintering melamine sponge, and the obtained carbon framework material has no Ag particles attached, which reduces the filtration effect of heavy metal ions in the water treatment process, indicating that Ag modification can significantly improve the material performance.

[0087] The above embodiments describe the preparation method and effects of the application in detail, but the protection scope of the application is not limited to the above parameters, and any process adjustment based on the same principle belongs to the claim scope of the patent.

Claims

1. A water treatment material, characterized in that: The water treatment material is a porous self-supporting carbon skeleton material with silver particles attached; the porous self-supporting material is obtained by sintering melamine sponge at high temperature.

2. The method for preparing a water treatment material according to claim 1, wherein: The preparation method comprises: Obtaining a melamine sponge, and soaking the melamine sponge in a silver nitrate solution to obtain a first mixed raw material; placing the first mixed raw material in a microwave tube furnace and firing at a high temperature; the high temperature is 500° C. to 800° C.; After the first mixed raw material is fired at the high temperature, the water treatment material is obtained; the water treatment material is a porous self-supporting carbon skeleton material with silver particles attached.

3. The method for preparing a water treatment material according to claim 2, wherein: The method of obtaining a melamine sponge and soaking the melamine sponge in a silver nitrate solution to obtain a first mixed raw material comprises: The melamine sponge is 100 mg and the silver nitrate solution is 1000 ml; The soaking time is 120 minutes.

4. The method for preparing a water treatment material according to claim 2, wherein: Placing the first mixed raw material in a microwave tube furnace for high-temperature firing comprises: The high temperature is 500°C to 800°C, preferably 500°C.

5. The method for preparing a water treatment material according to claim 2, wherein: Placing the first mixed raw material in a microwave tube furnace for high-temperature firing comprises: The protective gas of the microwave tube furnace during the high-temperature firing process is any one of the following: A mixture of argon and hydrogen, argon or nitrogen.

6. The method for preparing a water treatment material according to claim 2, wherein: Placing the first mixed raw material in a microwave tube furnace for high-temperature firing comprises: The high temperature firing time is 33-35 minutes, and the heating rate is set at 15 degrees / minute.

7. The method for preparing a water treatment material according to any one of claims 2 to 6, characterized in that: The water treatment material is a porous self-supporting carbon skeleton material with silver particles attached, comprising: The porous self-supporting carbon skeleton material in the water treatment material is a carbon skeleton material having a combination of any one or more pore sizes of macropores, micropores and mesopores, wherein the macropores have a pore size greater than 50 nm, the micropores are 2 nm to 50 nm, and the mesopores have a pore size less than 2 nm.

8. The method for preparing a water treatment material according to any one of claims 2 to 6, characterized in that: The mass percentage of Ag particles and carbon skeleton material in the water treatment material is less than or equal to 2%.

9. Use of the water treatment material according to any one of claims 1 to 8 in a filter cup, characterized in that: The water treatment material is applied to a filter cup, wherein the water treatment material removes pollutants in the water body by physical adsorption and physical interception, wherein the pollutants include suspended matter and / or water-soluble pollutants.

10. The method for backwashing a water treatment material according to any one of claims 1 to 8, characterized in that: In the filtration stage, the liquid to be treated is made to flow from top to bottom through the water treatment material layer; In the backwash stage, when the filtration pressure difference or the operation time reaches the set value, the cleaning medium is made to flow through the water treatment material layer in reverse from bottom to top to remove the retained suspended matter.

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