An electrically driven adsorption-degradation coupling system based on two types of three-component composite sheets

Abstract

The application discloses a kind of electric drive adsorption-degradation coupling systems based on two kinds of three-component composite sheets.The two kinds of three-component composite sheets are composed of eutectic solvent, derived cellulose and metal organic framework or multi-walled carbon nanotube, which are simultaneously used as electrodes and adsorbate; after being connected with wires and power supply, the electric drive adsorption-degradation coupling system for removing water environmental pollutants represented by antibiotics and pigments is composed of electric adsorption cell, electric degradation cell, valve and switch. The preparation process of the two kinds of composite sheet electrodes is simple, the appearance is regular, and the composition is convenient to control; in application, it embodies good conductivity, ideal strength, stable state and other characteristics. By establishing the electric adsorption-degradation coupling system, the synergistic effect of each component of the composite sheet can be exerted, and the application way and form of the eutectic solvent-nanocomposite material are widened. In addition, the system operates in a safe voltage and current environment, and is designed scientifically and simply, easy to build, maintain and reuse.

Description

Technical Field

[0001] This invention belongs to the field of separation and degradation technology, and particularly relates to the application of a multi-task system related to eutectic solvents and nanomaterials in the separation and degradation of aquatic pollutants; specifically, it involves the removal of aquatic pollutants, such as antibiotics and pigments, from a composite sheet prepared with three components: eutectic solvent, carbon nanotubes or metal-organic framework, and derived cellulose, in an electrically driven system. Background Technology

[0002] Antibiotics and pigments are common pollutants in aquatic environments, posing a threat to ecosystems and human health. Treatment methods can be categorized into four types: biological, chemical, physical, and mixed approaches. Oxidative degradation, precipitation, condensation, membrane treatment, adsorption, distillation, and filtration are commonly used techniques in this field. Among these, adsorption is more widely used because it can also be used to enrich pollutants in water for subsequent analysis and monitoring. By using various adsorbents, including alumina, montmorillonite, kaolinite, graphene oxide, soil and sediment, activated carbon, and various nanomaterials, the adsorption and removal of common pollutants have been achieved. Furthermore, adsorption is often coupled with biodegradation, utilizing microorganisms to remove the enriched pollutants. This strategy is relatively mature and has been applied to wastewater treatment in the chemical and pharmaceutical industries. To improve processing efficiency, an electric field can be used to enhance physical adsorption and chemical degradation. An electrostatic field is formed between the electrodes by applying an external voltage. Charged particles are forced to move toward the electrode plate with the opposite charge by electrostatic force in the electrostatic field, forming an electric double layer on the surface of the electrode plate. When the potential of the electrode surface reaches a certain value, the concentration of ions in the electric double layer can be hundreds or thousands of times that of the bulk solution. Electric adsorption and degradation have many advantages: (1) Electric field-assisted technology has low pollution and high energy utilization, and is environmentally friendly; (2) Electric field-assisted process is simple to operate; (3) Electric field-assisted technology has high resource utilization and can separate substances with low content that are difficult to treat by conventional methods; Coupling the two processes can also give full play to the characteristics of complementary advantages and continuous operation.

[0003] Eutectic solvents are two- or three-component eutectic mixtures composed of hydrogen bond acceptors (such as quaternary ammonium salts) and hydrogen bond donors (such as amides, carboxylic acids, and polyols) in a stoichiometric ratio, with freezing points significantly lower than the melting points of their individual components. As a novel type of green solvent, eutectic solvents have attracted considerable attention due to their environmentally friendly properties and numerous superior physicochemical properties compared to conventional solvents. Their advantages in practical applications include designability, ease of preparation, multifunctionality, low vapor pressure, chemical stability, good conductivity, and a wide electrochemical window. Currently, various eutectic solvents are widely used in catalysis, separation, electrochemistry, nanomaterials, polymer science, environmental science, and other related fields, with some techniques already operating on a large scale. In previous electrochemical research, they have primarily been used as electrolytes to improve battery efficiency, as solvents to synthesize electrode materials with special functions, or for the electrodeposition of metals, alloys, and semiconductors. Furthermore, immobilizing eutectic solvents with different methods and supports facilitates their recovery and recycling, further reducing consumption and loss, and fully demonstrating their greenness and sustainability.

[0004] Metal-organic frameworks (MOFs) are a class of organic-inorganic hybrid nanomaterials derived from the periodic coordination of organic ligands and metal nodes. Combining the structural characteristics of rigid inorganic materials and flexible organic materials, they have attracted widespread attention and application since their emergence. They possess numerous advantages, including large specific surface area, high porosity, and tunable pore size. In the field of electrochemical technology, they have been initially used in the construction of novel sensors and for the sensitive and accurate detection of antibiotics, heavy metals, and tumor markers. The conductivity of most MOFs is relatively low, but this can be significantly enhanced by combining them with eutectic solvents. Furthermore, zeolite imidazole ester frameworks prepared from zinc salts and imidazole ligands represent an important subclass of MOFs, exhibiting a structure similar to aluminosilicate zeolites. They combine the advantages of both zeolites and MOFs, demonstrating not only stronger thermal and chemical stability than other MOFs but also higher specific surface area and pore volume. The specific surface area of ​​such MOFs can reach up to 1850 m². 2 / g, which is 2 to 6 times that of activated carbon and molecular sieve materials. It is mainly used in gas adsorption and separation, catalytic reactions, sensors, microelectronic devices, drug carriers, 3D printing, fluorescence detection, and many other fields.

[0005] The discovery of carbon nanotubes has opened up a new field of research on allotropes and nanomaterials within the carbon family. Classified by the number of graphite flakes, they can be divided into single-walled carbon nanotubes and multi-walled carbon nanotubes, the latter having a higher conductivity permeation threshold and being more rigid. These materials, with their unique mechanical, electrical, and chemical properties, as well as their distinctive quasi-one-dimensional tubular molecular structure and potential applications in high-tech fields, have rapidly become a research hotspot in chemistry, physics, and materials science. In this technological field, they can be used to separate, catalytically degrade, and adsorb organic pollutants in water (such as dioxins, chlorobenzene, antibiotics, etc.), heavy metal ions from various sources, and other environmentally harmful residues. Particularly in the electrochemical field, due to their excellent conductivity, catalytic activity, and large specific surface area, they can effectively promote electron transfer when used in chemical reactions. Practice has shown that carbon nanotubes, compared to traditional conductive agents, have better conductivity and require less dosage; even with very low addition amounts, they impart excellent and uniform conductivity to the material; moreover, compared to particulate conductive agents, tubular conductive agents have a larger aspect ratio, which is beneficial for forming conductive networks; therefore, they are very suitable for constructing electro-driven systems. Summary of the Invention

[0006] The purpose of this invention is to construct an electro-driven adsorption-degradation coupling system based on two types of three-component composite sheets. This system has a simple structure, convenient preparation of key components, mild operating conditions, ease of operation, and is easy to promote, requiring no complex equipment. The three-component composite sheets function as both electrodes and adsorbates. Through simple steps, derived cellulose is used to composite a eutectic solvent with carbon nanotubes or a metal-organic framework, resulting in a well-defined appearance, ideal strength, stable state, and significant effects. The eutectic solvent can also be replaced to create a series of products, greatly solving the problems of high cost, difficult recycling, and limited reusability associated with using these materials individually. The sheet electrodes are connected to a power source via wires, are usable when energized, have good conductivity, and operate under safe voltage and current conditions. After adsorption, the system can switch to desorption-degradation mode, driven by an electric field until pollutants are largely removed. The residual liquid is then discharged for the next round of use. The sheet electrodes do not disintegrate or lose components during water treatment, preventing environmental and object pollution. The entire system exhibits strong versatility, ease of construction, maintenance, and reuse.

[0007] Technical solution: To achieve the above objectives, an electro-driven adsorption-degradation coupling system based on two types of three-component composite sheets is proposed; the main components include the preparation of the two types of three-component composite sheets and the construction of the electro-driven adsorption-degradation coupling system to remove representative pollutants from water samples.

[0008] An electro-driven adsorption-degradation coupling system consisting of two types of three-component composite sheets, characterized in that the two types of three-component composite sheets are composed of a eutectic solvent, derived cellulose, and a metal-organic framework or multi-walled carbon nanotubes.

[0009] An electro-driven adsorption-degradation coupling system consisting of two types of three-component composite sheets, characterized in that the eutectic solvents used in the two types of three-component composite sheets include, but are not limited to, thymol / benzyl alcohol (1:1), thymol / phenyl salicylate (1:1), thymol / camphor (1:1), thymol / menthol (1:1) or thymol / octanol (1:1).

[0010] An electro-driven adsorption-degradation coupling system consisting of two types of three-component composite sheets, characterized in that the derived cellulose used in the two types of three-component composite sheets includes, but is not limited to, ethyl cellulose, methyl cellulose, carboxymethyl cellulose, hydroxypropyl cellulose, or hydroxypropyl methyl cellulose.

[0011] An electro-driven adsorption-degradation coupling system consisting of two types of three-component composite sheets, characterized in that the metal-organic framework used in the three-component composite sheets includes, but is not limited to, metal-organic frameworks prepared with zinc acetate and 2-methylimidazole.

[0012] An electro-driven adsorption-degradation coupling system comprising two types of three-component composite sheets, characterized in that the preparation steps of the eutectic solvent-metal-organic framework-derived cellulose composite sheet are as follows:

[0013] (1) Zinc acetate, 2-methylimidazole and eutectic solvent were uniformly dispersed in methanol at a mass ratio (g / g) of 3.3 / 1.5 / 0~3.3 / 1.5 / 1.0. Then, methanol was removed under reduced pressure, and deionized water was added for precipitation. The insoluble matter was collected by filtration, washed with water and methanol in turn, and dried under vacuum to obtain the eutectic solvent-metal-organic framework complex.

[0014] (2) Add 0.05 / 0.25~0.15 / 0.15 of the derivatized cellulose in a mass ratio (g / g) of 0.05 / 0.25~0.15 / 0.15 to the eutectic solvent-metal-organic framework complex, mix and grind thoroughly, and then pass through a 200-mesh sieve; then place it into a stainless steel tableting mold and press it into shape under a pressure of 5~20MPa.

[0015] An electro-driven adsorption-degradation coupling system consisting of two types of three-component composite sheets is characterized by the following steps in preparing the eutectic solvent-multi-walled carbon nanotube-derived cellulose composite sheet: multi-walled carbon nanotubes and eutectic solvent are mixed at a mass ratio (mg / mg) of 1 / 1 to 1 / 20 and stirred evenly to obtain the eutectic solvent-multi-walled carbon nanotube composite; then, derived cellulose is added to it at a mass ratio (g / g) of 0.05 / 0.25 to 0.15 / 0.15, mixed and thoroughly ground, and then passed through a 200-mesh sieve; finally, it is placed in a stainless steel compression mold and pressed into shape under a pressure of 5 to 20 MPa.

[0016] An electrically driven adsorption-degradation coupling system consisting of two types of three-component composite sheets is characterized in that the two types of composite sheets are used as electrodes and connected to a power source via wires, and then combined with an electro-adsorption cell, an electro-degradation cell, valves and switches to form an adsorption-degradation coupling system for removing pollutants from water.

[0017] An electro-driven adsorption-degradation coupling system consisting of two types of three-component composite sheets, characterized in that the specific implementation methods of the corresponding electro-driven adsorption and electro-driven degradation are as follows:

[0018] (1) In the electro-driven adsorption process, the eutectic solvent-metal-organic framework-derived cellulose composite sheet electrode is used as the positive electrode and the eutectic solvent-carbon nanotube-derived cellulose composite sheet electrode is used as the negative electrode. The two are fixed with platinum electrode clamps and placed in parallel in an adsorption cell containing water sample. The distance between the positive and negative electrodes can be adjusted according to the diameter of the adsorption cell. The composite sheet is connected to a regulated DC power supply using platinum wires to obtain a constant voltage.

[0019] (2) After step (1) is completed, the coupling system is switched to the desorption state; the composite electrode is regenerated by the eluent; the eluent flows into the degradation tank, peroxymonosulfonate and ferrous sulfate are added, and then a constant voltage is applied to complete the electro-driven degradation of pollutants in the eluent;

[0020] (3) Valve 1, valve 2, switch 1 and switch 2 are used to switch between electro-driven adsorption and electro-driven degradation processes. First, valve 1 is closed and switch 1 is opened to achieve electro-driven adsorption in the electro-adsorption cell containing the water sample. After the process is completed, valve 1 and valve 2 are opened to discharge the water sample. Then, the two valves are closed and the eluent is added to the electro-adsorption cell. After desorption is completed, valve 1 is opened to send the eluent into the electro-degradation cell. Then, switch 2 is opened to complete the electro-driven degradation process.

[0021] An electro-driven adsorption-degradation coupling system consisting of two types of three-component composite sheets is characterized in that, during the electro-driven adsorption process, a constant voltage is applied to the two types of composite electrode sheets, including but not limited to -2.5V to 2.5V.

[0022] An electro-driven adsorption-degradation coupling system consisting of two types of three-component composite sheets, characterized in that the constant voltage applied during the electro-driven degradation process includes, but is not limited to, 0~3V. Attached Figure Description

[0023] Figure 1(a) is a thymol / benzyl alcohol-metal-organic framework-microcrystalline cellulose composite sheet with a diameter of 13.02 mm and a thickness of 0.84 mm and its (b) scanning electron microscope image (b(1): front view, b(2): side view; in which the metal-organic framework is hexagonal and the microcrystalline cellulose has an almost spherical appearance); thymol / benzyl alcohol, metal-organic framework and microcrystalline cellulose are uniformly mixed from the front and cross-sectional views).

[0024] Figure 2 (a) is a thymol / benzyl alcohol-multi-walled carbon nanotube-ethyl cellulose composite sheet with a diameter of 13.34 mm and a thickness of 1.37 mm and its (b) scanning electron microscope image (b(1): front view, b(2): side view; in which the carbon nanotubes are tubular and the ethyl cellulose is nearly spherical); the ionic liquid, multi-walled carbon nanotubes and ethyl cellulose are uniformly mixed in both the front view and the cross-section image).

[0025] Figure 3 (a) Infrared spectrum of thymol / benzyl alcohol-metal-organic framework-microcrystalline cellulose composite sheet and (b) X-ray diffraction pattern of thymol / benzyl alcohol-metal-organic framework powder.

[0026] Figure 4 (a) Infrared spectrum of thymol / benzyl alcohol-multi-walled carbon nanotube-ethyl cellulose composite sheet and (b) X-ray diffraction pattern of thymol / benzyl alcohol-multi-walled carbon nanotube composite powder.

[0027] Figure 5 This is a schematic diagram of the system components. Detailed Implementation

[0028] The following provides a detailed description of specific embodiments of the present invention, but these embodiments are not intended to limit the scope of the invention. The endpoints and values ​​described herein are not limited to these precise ranges and values; these ranges should be understood to include values ​​close to these ranges. Non-essential modifications and adjustments made by those skilled in the art based on this invention still fall within the scope of the invention.

[0029] Example 1

[0030] The preparation steps of the eutectic solvent-metal-organic framework-microcrystalline cellulose composite tablet are as follows: (1) Zinc acetate, 2-methylimidazol and thymol / benzyl alcohol are uniformly dispersed in methanol at a mass ratio (g / g) of 3.3 / 1.5 / 1.0, and then methanol is removed under reduced pressure. Deionized water is added for precipitation. The insoluble matter is collected by filtration, washed with water and methanol in sequence, and dried under vacuum to obtain the eutectic solvent-metal-organic framework composite. (2) Ethyl cellulose at a mass ratio (g / g) of 0.15 / 0.15 is added to the thymol / benzyl alcohol-metal-organic framework composite. The mixture is mixed and ground thoroughly and then passed through a 200-mesh sieve. The mixture is then placed in a stainless steel tableting mold and pressed into shape under a pressure of 20 MPa.

[0031] Example 2

[0032] The difference between this embodiment and Embodiment 1 is that the thymol / benzyl alcohol used in the preparation of the eutectic solvent-metal-organic framework-microcrystalline cellulose composite sheet is replaced with thymol-phenyl salicylate; other specific implementation methods are the same as in Embodiment 1.

[0033] Example 3

[0034] The difference between this embodiment and Embodiment 1 is that the ethyl cellulose used in the preparation of the eutectic solvent-metal-organic framework-microcrystalline cellulose composite sheet is replaced with microcrystalline cellulose; other specific implementation methods are the same as in Embodiment 1.

[0035] Example 4

[0036] The difference between this embodiment and Embodiment 1 is that the mass ratio of zinc acetate, 2-methylimidazole, and thymol / benzyl alcohol used in the preparation of the eutectic solvent-metal-organic framework-microcrystalline cellulose composite sheet is replaced with 3.3 / 1.5 / 0.5; other specific implementation methods are the same as in Embodiment 1.

[0037] Example 5

[0038] The difference between this embodiment and Embodiment 1 is that the mass ratio (g / g) of thymol / benzyl alcohol-metal-organic framework and ethyl cellulose in the preparation of the eutectic solvent-metal-organic framework-microcrystalline cellulose composite sheet is replaced with 0.1 / 0.2; other specific implementation methods are the same as in Embodiment 1.

[0039] Example 6

[0040] The difference between this embodiment and Embodiment 1 is that the pressure used in the preparation of the eutectic solvent-metal-organic framework-microcrystalline cellulose composite sheet is replaced with 10 MPa; other specific implementation methods are the same as in Embodiment 1.

[0041] Example 7

[0042] The preparation steps of the eutectic solvent-multi-walled carbon nanotube-ethyl cellulose composite sheet are as follows: multi-walled carbon nanotubes and thymol / benzyl alcohol are mixed at a mass ratio (mg / mg) of 1 / 1 and stirred evenly to obtain a thymol / benzyl alcohol-multi-walled carbon nanotube composite; then ethyl cellulose with a mass ratio (g / g) of 0.15 / 0.15 is added to it, mixed and ground thoroughly, and then passed through a 200-mesh sieve; then it is placed in a stainless steel tableting mold and pressed into shape under a pressure of 20 MPa.

[0043] Example 8

[0044] The difference between this embodiment and Example 7 is that the thymol / benzyl alcohol used in the preparation of the eutectic solvent-multi-walled carbon nanotube-ethyl cellulose composite sheet is replaced with thymol-phenyl salicylate; other specific implementation methods are the same as in Example 7.

[0045] Example 9

[0046] The difference between this embodiment and Embodiment 7 is that the ethyl cellulose used in the preparation of the eutectic solvent-multi-walled carbon nanotube-ethyl cellulose composite sheet is replaced with microcrystalline cellulose; other specific implementation methods are the same as in Embodiment 7.

[0047] Example 10

[0048] The difference between this embodiment and Embodiment 7 is that the pressure used in the preparation of the eutectic solvent-multi-walled carbon nanotube-ethyl cellulose composite sheet is replaced with 10 MPa; other specific implementation methods are the same as in Embodiment 7.

[0049] Example 11

[0050] This embodiment is an application example of an electro-driven adsorption-degradation coupling system consisting of two types of three-component composite sheets for the removal of ciprofloxacin from water samples:

[0051] (1) In the electro-driven adsorption process, the thymol / benzyl alcohol-metal-organic framework-microcrystalline cellulose composite sheet electrode prepared in Example 1 was used as the positive electrode, and the thymol / benzyl alcohol-multi-walled carbon nanotube-ethyl cellulose composite sheet electrode prepared in Example 7 was used as the negative electrode. The two were fixed with platinum electrode clamps and placed in parallel in an adsorption cell containing 50 mL of ciprofloxacin aqueous solution with a concentration of 15 mg / L. The distance between the positive and negative electrodes was 1.5 cm. The composite sheet was connected to a regulated DC power supply using platinum wires to obtain a constant voltage of 3 V, and the concentration was continuously detected during the adsorption process.

[0052] (2) After step (1) is completed, the coupling system is switched to desorption state; the composite electrode is regenerated by 10 mL of 20% methanol-water; the eluent flows into the degradation tank, and 3 mg / mL peroxymonosulfonate and 3 mg / mL ferrous sulfate are added according to the volume of the desorption liquid. Then a constant voltage of 3V is applied, and the concentration is continuously monitored during the degradation process.

[0053] (3) Valve 1, valve 2, switch 1 and switch 2 are used to switch between electro-driven adsorption and electro-driven degradation processes. First, valve 1 is closed and switch 1 is opened to achieve electro-driven adsorption in the electro-adsorption cell containing ciprofloxacin. After the process is completed, valves 1 and 2 are opened to discharge the water sample. Then, the two valves are closed and the eluent is added to the electro-adsorption cell. After desorption is completed, valve 1 is opened to send the eluent containing ciprofloxacin into the electro-degradation cell. Then, switch 2 is opened to start the electro-driven degradation process.

[0054] Example 12

[0055] The difference between this embodiment and Embodiment 11 is that the electro-driven adsorption-degradation coupling system of the two types of three-component composite sheets is used to remove methylene blue from water samples, and the eluent composition is replaced with 20% methanol-0.5M NaCl solution. Other specific implementation methods are the same as in Embodiment 11.

[0056] Example 13

[0057] The difference between this embodiment and embodiment 11 is that a constant voltage of 1.5V is used in the electro-driven adsorption process; other specific implementation methods are the same as in embodiment 11.

[0058] Example 14

[0059] The difference between this embodiment and embodiment 11 is that a constant voltage of 1.5V is used during the electrically driven degradation process; other specific implementation methods are the same as in embodiment 11.

[0060] Example 15

[0061] The difference between this embodiment and Embodiment 11 is that 2 mg / mL of peroxymonosulfonate is added according to the volume of the water sample during the electro-driven degradation process; other specific implementation methods are the same as in Embodiment 11.

[0062] Example 16

[0063] The difference between this embodiment and Example 11 is that 2 mg / mL of ferrous sulfate is added during the electro-driven degradation process according to the volume of the desorption liquid; other specific implementation methods are the same as in Example 11.

[0064] Example 17

[0065] Based on the reported method, a configuration of 4.6×250mm C was adopted. 18 The concentrations of ciprofloxacin and methylene blue were determined by high-performance liquid chromatography (HPLC) using a 5 µm column. The analytical conditions for ciprofloxacin included: detection wavelength set at 212 nm, column temperature at 35 °C, mobile phase of methanol:0.02 M NaH₂PO₄ aqueous solution (pH 3.5) = 60:40 (V / V), flow rate of 1 mL / min; and a standard curve of y = 4.2447x - 3.034 (R²). 2 =0.9956), where y is the peak area and x is the concentration of ciprofloxacin (mg / L). The analytical conditions for methylene blue included: detection wavelength of 600 nm, column temperature of 35 °C, mobile phase of acetonitrile:0.125 M NH4Ac aqueous solution (adjusted to pH 4.5 with acetic acid) = 80:20 (V / V), flow rate of 1 mL / min; and a standard curve of y = 89.007x - 36.227 (R² = 0.9956), where y is the peak area and x is the concentration of ciprofloxacin (mg / L). 2 =0.9998), where y is the chromatographic peak area and x is the methylene blue concentration (mg / L).

[0066] The adsorption rate of ciprofloxacin or methylene blue was calculated using formula (1):

[0067]

[0068] In the above formula, A (%) represents the adsorption efficiency. C0 and C1 (mg / L) are the concentrations of ciprofloxacin or methylene blue before and after adsorption, respectively.

[0069] Based on the results determined by the above quantitative analysis method, and combined with formula (1), the adsorption rates of ciprofloxacin and methylene blue after 24 hours in the electro-driven adsorption process corresponding to Examples 11 and 12 were calculated to be 90.5% and 94.9%, respectively.

[0070] The degradation rate of ciprofloxacin or methylene blue was calculated using formula (2):

[0071]

[0072] In the above formula, B (%) represents the degradation efficiency. C 0 and C 1 (mg / L) represents the concentration of ciprofloxacin or methylene blue before and after degradation, respectively.

[0073] Based on the results measured by the above quantitative analysis method, and combined with formula (2), the degradation rates of ciprofloxacin and methylene blue after 20 minutes in the electrically driven degradation process corresponding to Examples 11 and 12 were calculated to be 98.0% and 95.5%, respectively.

Claims

1. An electro-driven adsorption-degradation coupling system consisting of two types of three-component composite sheets, characterized in that, Two types of three-component composite sheets are composed of a eutectic solvent, derived cellulose, and a metal-organic framework or multi-walled carbon nanotubes; the preparation steps of the eutectic solvent-metal-organic framework-derived cellulose composite sheet are as follows: (1) Zinc acetate, 2-methylimidazole and eutectic solvent were uniformly dispersed in methanol at a mass ratio of 3.3:1.5:0~3.3:1.5:1.0 g / g. Then, methanol was removed under reduced pressure, and deionized water was added for precipitation. The insoluble matter was collected by filtration, washed with water and methanol in sequence, and dried under vacuum to obtain the eutectic solvent-metal-organic framework complex. (2) Add a derivative cellulose with a mass ratio of 0.05:0.25~0.15:0.15 g / g to the eutectic solvent-metal-organic framework complex, mix and grind thoroughly, and then pass through a 200-mesh sieve; then place it into a stainless steel tableting mold and press it into shape under a pressure of 5~20MPa. The preparation steps of the eutectic solvent-multi-walled carbon nanotube-derived cellulose composite sheet are as follows: Multi-walled carbon nanotubes and eutectic solvent are mixed at a mass ratio of 1:1 to 1:20 mg / mg and stirred evenly to obtain the eutectic solvent-multi-walled carbon nanotube composite; then, derived cellulose is added to it at a mass ratio of 0.05:0.25 to 0.15:0.15 g / g, mixed and thoroughly ground, and then passed through a 200-mesh sieve; then, it is placed in a stainless steel tableting mold and pressed into shape under a pressure of 5 to 20 MPa. Using the above two types of three-component composite sheets as electrodes, and connecting them to a power source via wires, they are combined with an electro-adsorption cell, an electro-degradation cell, valves, and switches to form an adsorption-degradation coupling system for removing pollutants from water.

2. The electro-driven adsorption-degradation coupling system of two types of three-component composite sheets according to claim 1, characterized in that, The eutectic solvents used in the two types of three-component composite tablets are 1:1 thymol / benzyl alcohol, 1:1 thymol / phenyl salicylate, 1:1 thymol / camphor, 1:1 thymol / menthol, or 1:1 thymol / octanol.

3. The electrically driven adsorption-degradation coupling system of two types of three-component composite sheets according to claim 1, characterized in that, The derived cellulose used in the two types of three-component composite tablets includes ethyl cellulose, methyl cellulose, carboxymethyl cellulose, hydroxypropyl cellulose, or hydroxypropyl methyl cellulose.

4. The electrically driven adsorption-degradation coupling system of two types of three-component composite sheets according to claim 1, characterized in that, The specific implementation methods of the corresponding electro-driven adsorption and electro-driven degradation are as follows: (1) In the electro-driven adsorption process, the eutectic solvent-metal-organic framework-derived cellulose composite sheet electrode is used as the positive electrode and the eutectic solvent-carbon nanotube-derived cellulose composite sheet electrode is used as the negative electrode. The two are fixed with platinum electrode clamps and placed in parallel in an electro-adsorption cell containing water sample. The distance between the positive and negative electrodes is adjusted according to the diameter of the electro-adsorption cell. The composite sheet is connected to a regulated DC power supply using platinum wires to obtain a constant voltage. (2) After step (1) is completed, the coupling system is switched to the desorption state; the composite electrode is regenerated by the eluent; the eluent flows into the electrodegradation cell, peroxymonosulfonate and ferrous sulfate are added, and then a constant voltage is applied to complete the electro-driven degradation of pollutants in the eluent; (3) Valve 1, valve 2, switch 1 and switch 2 are used to switch between electro-driven adsorption and electro-driven degradation processes. First, valve 1 is closed and switch 1 is opened to achieve electro-driven adsorption in the electro-adsorption cell containing the water sample. After the process is completed, valve 1 and valve 2 are opened to discharge the water sample. Then, the two valves are closed and the eluent is added to the electro-adsorption cell. After desorption is completed, valve 1 is opened to send the eluent into the electro-degradation cell. Then, switch 2 is opened to complete the electro-driven degradation process.

5. The electro-driven adsorption-degradation coupling system of two types of three-component composite sheets according to claim 4, characterized in that, In the above-mentioned electro-driven adsorption process, the constant voltage applied to the two types of three-component composite sheet electrodes includes -2.5V to 2.5V.

6. The electro-driven adsorption-degradation coupling system of two types of three-component composite sheets according to claim 4, characterized in that, The constant voltage applied during the electro-driven degradation process ranges from 0 to 3V.

Images