Electro-enhanced adsorption filtration-based water treatment material, preparation method therefor and use thereof

Abstract

The present invention relates to the technical field of high polymer materials. Specifically disclosed are an electro-enhanced adsorption filtration-based water treatment material, a preparation method therefor, and a use thereof. The method comprises the following steps: (1) ultrasonically cleaning a melamine sponge, drying the melamine sponge, placing the melamine sponge into a tube furnace, introducing a protective gas, setting a heating rate to be 4-6ºC·min-1, preheating, then continuing heating to 900-1100ºC, maintaining the heat, and cooling to room temperature to obtain an ultra-light flexible carbon sponge; and (2) dissolving tris(hydroxymethyl)aminomethane in a solvent to obtain a solution, adjusting the pH to 8.4-8.6, then adding dopamine and polyethyleneimine, mixing, adding the ultra-light flexible carbon sponge, and stirring for a reaction for 10-14 h to prepare the electro-enhanced adsorption filtration-based water treatment material. According to the present invention, an N-rich melamine sponge is used as a precursor and has a larger specific surface area; after being subjected to high-temperature carbonization in an inert gas, the sponge has good conductivity; and after being modified with dopamine and polyethyleneimine, the adsorption potential of the sponge is improved.

Description

A water treatment material for electrically enhanced adsorption filtration, and its preparation method and application Technical Field

[0001] The present invention relates to the technical field of polymer materials, and in particular to a water treatment material for electrically enhanced adsorption filtration, a preparation method thereof, and an application thereof. Background Art

[0002] As the global population continues to grow, water resource issues are becoming increasingly prominent. According to a United Nations report, approximately one-quarter of the world's population lives in areas with water scarcity, and this number is expected to grow in the coming decades. At the same time, factors such as overexploitation, pollution, and climate change also threaten global water supplies. In many regions, rapid urbanization and industrialization are creating increasingly pressing water resource challenges. These challenges not only affect people's daily lives but also have profound impacts on the environment, agriculture, and industry.

[0003] To address water scarcity and water pollution, researchers and engineers are working tirelessly to find efficient and sustainable water treatment methods. While traditional water treatment methods, such as chemical and biological treatment, can purify water to a certain extent, they also present significant challenges. For example, chemical methods often consume significant amounts of energy and chemicals, while biological methods are limited by environmental factors such as climate and water quality. Therefore, there is an urgent need for new water treatment technologies that can efficiently remove pollutants from water.

[0004] Among various water treatment technologies, adsorption technology has attracted much attention due to its high efficiency and universality. Adsorption is a method of removing pollutant particles from water by aggregating them on the surface or internal structure of the adsorbent. Compared with other treatment methods, adsorption technology has many advantages, such as simple operation, no restrictions on environmental factors, and high applicability to a variety of pollutants. Due to its flexibility and high efficiency, adsorption technology has been widely used in water treatment, wastewater treatment, drinking water purification and other fields. However, traditional adsorption materials such as activated carbon and lignin still have problems such as low adsorption efficiency and difficulty in regeneration. For this reason, it is necessary to provide a water treatment material for electrically enhanced adsorption filtration and its preparation method and application, so as to produce efficient and recyclable adsorption materials and further improve the removal efficiency of pollutants.

[0005] Summary of the Invention

[0006] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the present invention proposes a water treatment material for electrically enhanced adsorption filtration and its preparation method and application, so as to produce a highly efficient and recyclable adsorption material, further improve the removal efficiency of pollutants, and improve the regeneration efficiency of the adsorbent.

[0007] A first aspect of the present invention provides a method for preparing a water treatment material for electrically enhanced adsorption filtration.

[0008] Specifically, the following steps are included:

[0009] (1) Ultrasonic cleaning of melamine sponge, drying, placing in a tube furnace, introducing protective gas, setting the heating rate to 4-6 ° C min -1 After preheating, the temperature is continued to rise to 900-1100°C, kept warm, and cooled to room temperature to obtain an ultra-light and flexible carbon sponge;

[0010] (2) Dissolve tris(hydroxymethyl)aminomethane in a solvent to obtain a tris(hydroxymethyl)aminomethane solution, adjust the pH to 8.4-8.6, add dopamine and polyethyleneimine, mix, add ultralight flexible carbon sponge, stir and react for 10-14 hours, and prepare an electrically enhanced adsorption and filtration water treatment material.

[0011] Preferably, in step (1), the step of placing in a tube furnace further comprises first placing the dried melamine sponge in a corundum boat, and then placing the corundum boat in the tube furnace.

[0012] Further preferably, the tube furnace is a quartz tube furnace.

[0013] Preferably, in step (1), the ultrasonic cleaning time is 8-12 minutes.

[0014] Further preferably, the ultrasonic cleaning time is 10 minutes.

[0015] Preferably, in step (1), the rate of introducing the protective gas is 80-120 mL / min.

[0016] Further preferably, in step (1), the rate of introducing the protective gas is 100 mL / min.

[0017] Preferably, in step (1), the melamine sponge is a cylinder with a bottom diameter of 0.5-1.5 cm and a height of 4-6 cm.

[0018] Further preferably, the melamine sponge is a cylinder with a bottom diameter of 1 cm and a height of 5 cm.

[0019] Preferably, in step (1), the drying temperature is 100-110° C. and the drying time is 8-16 hours.

[0020] Further preferably, in step (1), the drying temperature is 105° C. and the drying time is 8-16 h.

[0021] Preferably, in step (1), the protective gas includes at least one of Ar, N2, and H2.

[0022] Preferably, in step (1), the preheating temperature is 200-300° C. and the preheating time is 20-40 min.

[0023] More preferably, the preheating temperature is 250° C. and the preheating time is 30 minutes.

[0024] Preferably, in step (1), the insulation time is 100-150 minutes.

[0025] More preferably, the insulation time is 120 minutes.

[0026] Preferably, in step (1), the temperature is continued to be raised to 1000°C.

[0027] Preferably, in step (1), the heating rate is set to 5°C·min -1 .

[0028] Preferably, in step (2), the mass concentration of the tris(hydroxymethyl)aminomethane solution is 0.1-1%.

[0029] More preferably, the mass concentration of the tris(hydroxymethyl)aminomethane solution is 0.6%.

[0030] Preferably, in step (2), the mass ratio of dopamine to polyethyleneimine is 1:1-4.

[0031] Further preferably, the mass ratio of dopamine to polyethyleneimine is 1:2.

[0032] Preferably, in step (2), the solvent is ultrapure water.

[0033] Preferably, in step (2), the pH is adjusted to 8.5.

[0034] A second aspect of the present invention provides a water treatment material for electrically enhanced adsorption filtration.

[0035] Specifically, the water treatment material for electrically enhanced adsorption filtration is prepared by the preparation method of the first aspect.

[0036] A third aspect of the present invention provides an application of an electrically enhanced adsorption and filtration water treatment material in the adsorption and removal of a broad spectrum of pollutants in water.

[0037] Preferably, the water treatment material for electrically enhanced adsorption filtration has at least one of the following functions (1)-(2):

[0038] (1) The adsorption capacity of water treatment materials for electrically enhanced adsorption filtration is enhanced under the action of the electric field, thereby improving the adsorption efficiency of organic matter and nutrients in water;

[0039] (2) The pore size of the water treatment material for electrically enhanced adsorption filtration is adjustable. Filtration is performed during compression, allowing the sponge to adsorb pollutants in a compressed state. Backwashing is performed during decompression, achieving efficient adsorption and regeneration of the material.

[0040] Preferably, the broad-spectrum pollutants in water bodies include total suspended solids, total organic carbon, ammonia nitrogen, phosphates, and organic matter.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] (1) The present invention utilizes N-rich melamine sponge as a precursor, which has a larger specific surface area;

[0043] (2) The sponge has good electrical conductivity after high-temperature carbonization by inert gas;

[0044] (3) Dopamine and polyethyleneimine were modified to prepare water treatment materials with electrically enhanced adsorption and filtration, further improving the capacitance performance and hydrophilicity of carbon sponge and increasing its adsorption potential;

[0045] (4) Using the electric field to significantly improve the adsorption efficiency of organic matter and nutrients in water;

[0046] (5) By utilizing the compressibility of water treatment materials for electrically enhanced adsorption filtration, the sponge can be used to adsorb pollutants in a compressed state and backwashed in a decompressed state, thereby achieving efficient adsorption and regeneration of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 is a schematic diagram of the reaction system structure;

[0048] FIG2 is a diagram showing the TOC and SS removal effects of the water treatment material using electrical enhanced adsorption filtration in Example 1;

[0049] FIG3 is a diagram showing the effect of the water treatment material for electrically enhanced adsorption filtration in Example 1 on the removal of ammonia nitrogen and phosphate;

[0050] Figure 4 shows the backwash desorption of NH4 in the decompression / compression state of the water treatment material of the electrically enhanced adsorption filtration of Example 1 + Efficiency graph;

[0051] Figure 5 shows the backwash desorption of PO4 in the decompression / compression state of the water treatment material of the electrically enhanced adsorption filtration of Example 1 3- Efficiency graph;

[0052] FIG6 is a cyclic stability diagram of the phosphorus removal performance of the water treatment material for electrically enhanced adsorption filtration in Example 1;

[0053] FIG7 is a diagram showing the removal effect of organic pollutants by the water treatment material of Example 1 through electrical enhanced adsorption filtration;

[0054] FIG8 is a diagram showing the removal effect of TOC and SS by ultralight flexible carbon sponge in Comparative Example 1;

[0055] FIG9 is a diagram showing the removal effect of ammonia nitrogen and phosphate by the ultra-light flexible carbon sponge in comparative example 1. DETAILED DESCRIPTION

[0056] In order to make the technical solution of the present invention more clearly understood by those skilled in the art, the following examples are given for illustration. It should be noted that the following examples do not limit the scope of protection claimed by the present invention.

[0057] Unless otherwise specified, the raw materials, reagents, or devices used in the following examples can be obtained from conventional commercial sources or by existing known methods.

[0058] Example 1

[0059] Water treatment material for electrically enhanced adsorption filtration and preparation method thereof.

[0060] The specific steps include:

[0061] (1) Commercial melamine sponge was cut into cylinders with a bottom diameter of 1 cm and a height of 5 cm. Ultrasonic cleaning was performed in an ultrasonic cleaner with ultrapure water for 10 min. The sponge was placed in a 105°C oven and dried for 16 h to remove the moisture adsorbed by the sponge during the cleaning process. The cleaned sponge was placed in a corundum boat to make the heat transfer more uniform. The boat was placed in a quartz tube furnace and Ar / H2 was introduced as a protective gas with a ventilation rate of 100 mL / min. The heating rate of the tube furnace was set to 5°C min -1 , preheated at 250℃ for 30min to remove part of the bound water of the sponge, then continued to heat up to 1000℃, kept warm at this temperature for 120min, and then naturally cooled slowly to room temperature to obtain an ultra-light and flexible carbon sponge.

[0062] (2) 0.6 g of tris(hydroxymethyl)aminomethane (Tris) was dissolved in 100 mL of ultrapure water. The pH of the tris(hydroxymethyl)aminomethane solution was approximately 10.5. The pH was adjusted to 8.5 using dilute hydrochloric acid. 0.2 g of dopamine (DA) and 0.4 g of polyethyleneimine (PEI) were then added and mixed. An ultralight flexible carbon sponge was placed in the mixture and stirred on a shaker for 12 h to produce a water treatment material with electrically enhanced adsorption and filtration.

[0063] Comparative Example 1

[0064] Ultralight flexible carbon sponge and preparation method thereof.

[0065] The difference from Example 1 is that Comparative Example 1 does not contain the step of amino modification, and specifically includes the following steps:

[0066] (1) Commercial melamine sponge was cut into cylinders with a bottom diameter of 1 cm and a height of 5 cm. Ultrasonic cleaning was performed in an ultrasonic cleaner with ultrapure water for 10 min. The sponge was placed in a 105°C oven and dried for 16 h to remove the moisture adsorbed by the sponge during the cleaning process. The cleaned sponge was placed in a corundum boat to make the heat transfer more uniform. The boat was placed in a quartz tube furnace and Ar / H2 was introduced as a protective gas with a ventilation rate of 100 mL / min. The heating rate of the tube furnace was set to 5°C min -1 , preheated at 250℃ for 30min to remove part of the bound water of the sponge, then continued to heat up to 1000℃, kept warm at this temperature for 120min, and then naturally cooled slowly to room temperature to obtain an ultra-light and flexible carbon sponge.

[0067] Comparative Example 2

[0068] Amino-modified sponge and preparation method thereof.

[0069] The difference from Example 1 is that Comparative Example 2 does not contain the step of carbonizing the melamine sponge, and specifically includes the following steps:

[0070] (1) Dissolve 0.6 g of tris(hydroxymethyl)aminoethane (Tris) in 100 mL of ultrapure water. The pH of the solution is approximately 10.5. Adjust the pH to 8.5 with dilute hydrochloric acid. Add 0.2 g of dopamine (DA) and 0.4 g of polyethyleneimine (PEI) and mix. Place a commercial melamine sponge in the mixture and stir on a shaker for 12 h to obtain an amino-modified sponge.

[0071] Adsorption removal performance test:

[0072] 1. Adsorption and removal of total suspended solids (SS) and total organic carbon (TOC) in water without electric field enhancement.

[0073] Testing was assisted using the reaction system shown in Figure 1, which consists of a reactor, peristaltic pump, water storage tank, and DC power supply. Domestic sewage was used as the water sample to be purified, and three pieces of the electrically enhanced adsorption filtration water treatment material prepared in Example 1 were placed at the anode and cathode, respectively. As shown in Figure 2, after 150 minutes of filtration, 63% of TOC and 78% of SS were removed.

[0074] 2. Adsorption and removal of nitrogen and phosphorus in water under electric field enhancement.

[0075] Using the reaction system shown in Figure 1, we conducted experiments using simulated wastewater prepared with ammonium chloride and sodium dihydrogen phosphate. The ammonia nitrogen concentration was 20 mg / L, and the phosphate concentration was 2 mg / L. Three pieces of the electrically enhanced adsorption and filtration water treatment material prepared in Example 1 were placed in each of the cathode and anode. As shown in Figure 3, within a 150-minute treatment time and at a 2V electric field, 95% ammonia nitrogen and phosphate removal was achieved.

[0076] 3. Cyclic stability test.

[0077] After adsorption saturation, the use of decompression backwashing can achieve faster desorption of nitrogen and phosphorus ions (NH4 + :7vs.11min; PO4 3- : 6 vs. 11 min) (as shown in Figures 4 and 5). Using the decompression backwashing method for desorption, the water treatment material prepared in Example 1 can achieve a removal efficiency of about 95% after 10 cycle experiments (as shown in Figure 6).

[0078] 4. Adsorb and remove organic pollutants in water.

[0079] The reaction system shown in Figure 1 was used for auxiliary testing, with carbamazepine and Acid Orange 7 serving as cations and anions representing organic pollutants. Three pieces of the electrically enhanced adsorption and filtration water treatment material prepared in Example 1 were placed at the anode and cathode, respectively. The initial concentrations of carbamazepine and Acid Orange 7 were 50 mg / L. As shown in Figure 7, the removal rates of both carbamazepine and Acid Orange 7 were significantly improved under the action of the electric field.

[0080] 5. Adsorption and removal of total suspended solids (SS) and total organic carbon (TOC) in water without electric field enhancement.

[0081] The reaction system shown in Figure 1 was used for auxiliary testing, with no voltage applied. Domestic sewage was used as the water sample to be purified, and three amino-modified sponges from Comparative Example 2 were placed at the anode and cathode, respectively. As shown in Figure 8, after 150 minutes of filtration, 43% of TOC and 40% of SS were removed.

[0082] 6. Adsorption and removal of nitrogen and phosphorus in water under electric field enhancement.

[0083] Using the reaction system shown in Figure 1, we conducted experiments using simulated wastewater prepared with ammonium chloride and sodium dihydrogen phosphate. The ammonia nitrogen concentration was 20 mg / L, and the phosphate concentration was 2 mg / L. Three ultralight, flexible carbon sponges from Comparative Example 1 were placed at the cathode and anode, respectively. As shown in Figure 9, within a 150-minute treatment time and at a 2V electric field, 36% ammonia nitrogen and 45% phosphate removal were achieved.

[0084] The above describes in detail the preferred embodiments of the present invention. It should be understood that those skilled in the art can make numerous modifications and variations based on the concepts of the present invention without inventive effort. Therefore, any technical solutions derived from modifications, equivalent substitutions, improvements, etc. made by those skilled in the art based on the concepts of the present invention through logical analysis, reasoning, or limited experimentation on the basis of the prior art shall be within the scope of protection defined by the claims.

Claims

1. A method for preparing a water treatment material for electrically enhanced adsorption filtration, characterized in that: The following steps are involved: (1) Ultrasonic cleaning of melamine sponge, drying, placing in a tube furnace, introducing protective gas, setting the heating rate to 4-6 ° C min -1 After preheating, the temperature is continued to rise to 900-1100°C, kept warm, and cooled to room temperature to obtain an ultra-light and flexible carbon sponge; (2) Dissolve tris(hydroxymethyl)aminomethane in a solvent to obtain a tris(hydroxymethyl)aminomethane solution, adjust the pH to 8.4-8.6, add dopamine and polyethyleneimine, mix, add ultralight flexible carbon sponge, stir and react for 10-14 hours, and prepare an electrically enhanced adsorption and filtration water treatment material.

2. The preparation method according to claim 1, characterized in that In step (1), the step of placing the sponge in a tube furnace further comprises placing the dried melamine sponge in a corundum boat, and then placing the corundum boat in the tube furnace.

3. The preparation method according to claim 1, characterized in that In step (1), the rate of introducing the protective gas is 80-120 mL / min.

4. The preparation method according to claim 1, characterized in that In step (1), the protective gas includes at least one of Ar, N2, and H2.

5. The preparation method according to claim 1, characterized in that In step (1), the preheating temperature is 200-300° C. and the preheating time is 20-40 minutes.

6. The preparation method according to claim 1, characterized in that In step (2), the mass concentration of the tris(hydroxymethyl)aminomethane solution is 0.1-1%.

7. The preparation method according to claim 1, characterized in that In step (2), the mass ratio of dopamine to polyethyleneimine is 1:1-4.

8. A water treatment material for electrically enhanced adsorption filtration, characterized in that: The water treatment material for electrically enhanced adsorption filtration is prepared by the preparation method according to any one of claims 1 to 7.

9. Use of the electrically enhanced adsorption and filtration water treatment material of claim 8 in the adsorption and removal of a wide spectrum of pollutants in water.

10. The use according to claim 9, characterized in that The water treatment material for electrically enhanced adsorption filtration has at least one of the following functions (1)-(2): (1) The adsorption capacity of water treatment materials for electrically enhanced adsorption filtration is enhanced under the action of the electric field, thereby improving the adsorption efficiency of organic matter and nutrients in water; (2) The pore size of the water treatment material for electrically enhanced adsorption filtration is adjustable. Filtration is performed during compression, allowing the sponge to adsorb pollutants in a compressed state. Backwashing is performed during decompression, achieving efficient adsorption and regeneration of the material.

Images