Nanoarray material for electrochemically removing chloride ions from circulating water in coal-fired power plants, preparation method thereof and application thereof

Abstract

This application belongs to the fields of environmental protection materials and water treatment in coal-fired power plants. This application proposes a nanoarray material for electrochemically removing chloride ions in the circulating water of coal-fired power plants, its preparation method and application. The nanoarray material uses surface-modified carbonized polyacrylamide submicron particles as the core, a composite oxide of TiO2 and CeO2 as the chloride ion remover, and carbonized paper as the substrate. Based on the mass of the carbonized paper, the mass percentage of the core is 5% - 8%, the mass percentage of the chloride ion remover is 3% - 4%, and the mass ratio of TiO2 and CeO2 in the chloride ion remover is 1:(0.5 - 1). The nanoarray material proposed in this application not only has the high conductivity of carbon spheres but also has the excellent redox performance of titanium-cerium composite oxides. When the oxides grow on the surface of the carbon spheres, nanochannels will also be formed, enabling excellent adsorption, activation, and conversion performance during the electrocatalytic removal of chloride ions under direct current.

Description

Technical Field

[0001] This application relates to the fields of environmental protection materials and water treatment in coal-fired power plants. Specifically, it relates to a nanoarray material for electrochemically removing chloride ions from the circulating water of coal-fired power plants, and its preparation method and application. Background Art

[0002] The circulating cooling water system is a key auxiliary system in coal-fired power plants, responsible for taking away the heat discharged from the condensers of generator sets and ensuring the normal operation of the units. However, when the circulating water contacts the air in the cooling tower, water evaporates, resulting in salt concentration, and the chloride ion concentration will increase significantly. As a strong corrosive ion, high-concentration chloride ions will damage the passivation film on the metal surface, accelerate equipment corrosion, especially for equipment made of materials such as stainless steel, greatly shorten the service life of the equipment, increase maintenance costs, and even cause leakage accidents. At the same time, when the circulating water is discharged, high-concentration chloride ions will pollute the water environment and cause harm to aquatic organisms. To ensure the safe and stable operation of the circulating cooling water system, reduce equipment corrosion and scaling, extend the service life of equipment, save energy, and protect the environment, the importance of removing chloride ions from the circulating water of coal-fired power plants has become increasingly prominent.

[0003] Currently, the most widely used reverse osmosis method uses a semi-permeable membrane to separate water and chloride ions under pressure drive, with advantages such as high desalination rate, simple operation, and high automation level. However, the high investment cost, membrane fouling problem, and high-pressure pump energy consumption problem also limit its application. The electrodialysis method uses anion and cation exchange membranes and a direct current electric field to make anions and cations migrate directionally to achieve the purpose of removing chloride ions. It has low energy consumption, simple operation, and small equipment floor area, and is suitable for removing medium-concentration chloride ions. However, its desalination rate is not as high as that of the reverse osmosis method, and membrane scaling and polarization phenomena are likely to occur. The ion exchange method uses the functional groups on ion exchange resins to exchange with chloride ions, with simple operation and low equipment investment, suitable for removing low-concentration chloride ions. However, the resin needs to be regenerated regularly, and the regeneration waste liquid also needs to be properly treated, and the treatment capacity is relatively limited. In addition, the chemical precipitation method forms insoluble precipitates of chloride ions by adding precipitants such as silver nitrate and calcium hydroxide, with simple operation and low cost, but the treatment efficiency is not high, and the generated precipitates are prone to cause secondary pollution. Although the above methods can treat chloride ions of different concentrations, their disadvantages are also very obvious. Therefore, developing a nanoarray material for electrochemically removing chloride ions from the circulating water of coal-fired power plants with high efficiency and low cost is one of the important development directions for the utilization of circulating water in coal-fired power plants. Summary of the Invention

[0004] This application aims to solve at least one of the technical problems in the related technologies to some extent.

[0005] The first aspect of the present application provides a nanoarray material for electrochemically removing chloride ions from the circulating water of a coal-fired power plant. The nanoarray material uses surface-modified carbonized polyacrylamide submicron particles as the core, a composite oxide of TiO2 and CeO2 as the chloride ion remover, and carbonized paper as the substrate, and is prepared by suspension polymerization - high-temperature carbonization - hydrothermal reaction - laser printing method;

[0006] Based on the mass of the carbonized paper, the mass percentage content of the core is 5% - 8%, and the mass percentage content of the chloride ion remover is 3% - 4%. Among them, the mass ratio of TiO2 to CeO2 in the chloride ion remover is 1:(0.5 - 1). Thus, the nanoarray material proposed in the present application not only has the high conductivity of carbon spheres but also has the excellent redox performance of titanium-cerium composite oxides. At the same time, when the oxide grows on the surface of the carbon spheres, nanopores will be formed. Therefore, it can have excellent adsorption, activation, and conversion performance during the direct current electrocatalytic removal of chloride ions.

[0007] The second aspect of the present application provides a method for preparing the nanoarray material provided in the first aspect of the present application. The method includes:

[0008] S10: Prepare carbonized polyacrylamide submicron particles

[0009] Weigh acrylamide and dissolve it in deionized water. Add polyvinyl alcohol and stir to disperse to form a slurry, then heat it in a water bath. After reaching the water bath heating reaction temperature, add an initiator and continue stirring until the polymerization reaction ends. After the reaction ends, filter and vacuum dry to obtain polyacrylamide powder. Then place the polyacrylamide powder in a tubular reaction furnace, introduce nitrogen, and heat it to carbonize to obtain carbonized polyacrylamide submicron particles. Finally, place the carbonized polyacrylamide submicron particles in a plasma surface treatment instrument. First, evacuate the plasma surface treatment instrument, then fill it with oxygen, and then perform surface treatment to obtain surface-modified carbonized polyacrylamide submicron particles;

[0010] S20: Load the chloride ion remover

[0011] Weigh a titanium salt and dissolve it in ethanol, then add the surface-modified carbonized polyacrylamide submicron particles to obtain a mixed slurry. The mixed slurry is continuously stirred and exposed to air. After the titanium salt hydrolysis is complete, add a cerium salt and deionized water, and place it in a hydrothermal reaction kettle for hydrothermal reaction. After the hydrothermal reaction ends, filter and then vacuum dry to obtain a mixed particle powder;

[0012] S30: Prepare the nanoarray material

[0013] Weigh the mixed particle powder and fill it into the toner cartridge. Then place the paper in the laser printer and start the laser printer for printing. After the mixed particle powder is printed on the paper, place the printed paper in a tubular reaction furnace, introduce nitrogen, and heat it up for carbonization. Finally, obtain the nanoarray material.

[0014] The method for preparing the nanoarray material proposed in this application uses acrylamide suspension polymerization to make polyacrylamide powder and then high-temperature carbonizes it into carbonized polyacrylamide submicron particles. The high conductivity of the carbonized polyacrylamide submicron particles is used to make up for the insufficient conductivity of the composite oxide, so that the composite oxide of TiO2 and CeO2 can have excellent electrochemical catalytic removal performance under a weak DC voltage. The surface of the carbonized polyacrylamide submicron particles is treated by plasma to increase the surface hydroxyl concentration. Finally, a hydrothermal reaction is used to convert titanium salt and cerium salt into oxides and grow on the surface of the surface-modified carbonized polyacrylamide submicron particles to form composite submicron spheres. To avoid the aggregation of the composite submicron spheres, which will cause a decrease in the electrochemical catalytic performance, the laser printing method is used to print them on the surface of the paper, and then the paper is converted into a sheet-like carbon material by high-temperature carbonization. Finally, the carbonized polyacrylamide submicron particles wrapped by the composite oxide of TiO2 and CeO2 are evenly dispersed on the surface of the sheet-like carbon material, that is, the nanoarray material.

[0015] According to some embodiments of the present application, the initiator includes potassium persulfate or sodium persulfate, and the mass ratio of acrylamide, deionized water, polyvinyl alcohol, and the initiator is 1:(10 - 20):(0.005 - 0.010):(0.001 - 0.005).

[0016] According to some embodiments of the present application, the temperature of the water bath heating is 50°C - 80°C, the time of the water bath heating is 6h - 12h, the temperature of the vacuum drying is 30°C - 60°C, the vacuum degree of the vacuum drying is 0.090MPa - 0.095MPa, and the time of the vacuum drying is 12h - 24h.

[0017] According to some embodiments of the present application, the rate of introducing nitrogen is 30mL / min - 60mL / min, the temperature of the temperature-rising carbonization is 600°C - 800°C, and the time of the temperature-rising carbonization is 6h - 12h.

[0018] According to some embodiments of the present application, the scanning rate of the plasma flame during the surface treatment is 20mm / s - 40mm / s, and the volume ratio of oxygen to the carbonized polyacrylamide submicron particles is 1:(30 - 60).

[0019] According to some embodiments of the present application, the titanium salt includes tetrabutyl titanate or tetraethyl titanate, the mass ratio of the titanium salt to the ethanol is 1:(30 - 60), and the stirring rate is 100 r / min - 200 r / min.

[0020] According to some embodiments of the present application, the cerium salt includes cerium nitrate hexahydrate or cerium chloride hexahydrate, and the mass ratio of the cerium salt to the deionized water is 1:(60 - 100).

[0021] According to some embodiments of the present application, the temperature of the hydrothermal reaction is 140°C - 160°C, the time of the hydrothermal reaction is 4 h - 8 h, the temperature of the vacuum drying is 30°C - 60°C, the vacuum degree of the vacuum drying is 0.090 MPa - 0.095 MPa, and the time of the vacuum drying is 12 h - 24 h.

[0022] The third aspect of the present application provides an application of the nanoarray material provided in the first aspect of the present application in removing chloride ions in the circulating water of a coal-fired power plant. Description of the Drawings

[0023] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, where:

[0024] Figure 1 It shows a schematic flow chart of a method for preparing a nanoarray material according to an embodiment of the present application.

[0025] Figure 2 It shows an FE-SEM image of the nanoarray material prepared in Example 1 of the present application.

[0026] Figure 3 It shows Figure 2 a partial enlarged view of Detailed Description of the Embodiments

[0027] The embodiments of the present application are described in detail below. The described embodiments are exemplary and are only used to explain the present application, and should not be construed as a limitation to the present application. For those technologies or conditions not specified in the embodiments, they shall be carried out according to the technologies or conditions described in the literature in the art or according to the product specifications. For the reagents or instruments not indicated by the manufacturer, they are all conventional products that can be obtained through commercial procurement.

[0028] The first aspect of the present application provides a nanoarray material for electrochemically removing chloride ions in the circulating water of a coal-fired power plant. The nanoarray material uses surface-modified carbonized polyacrylamide submicron particles as the core, a composite oxide of TiO2 and CeO2 as the chloride ion remover, and carbonized paper as the substrate, and is prepared by suspension polymerization - high-temperature carbonization - hydrothermal reaction - laser printing method;

[0029] Based on the mass of the carbonized paper, the mass percentage content of the core is 5% - 8%, and the mass percentage content of the chloride ion remover is 3% - 4%. Among them, the mass ratio of TiO2 to CeO2 in the chloride ion remover is 1:(0.5 - 1).

[0030] The nanoarray material provided by this application can achieve efficient removal of chloride ions from the circulating water in coal-fired power plants. This nanoarray material is prepared by suspension polymerization of acrylamide to form polyacrylamide powder and then high-temperature carbonization into carbonized polyacrylamide submicron particles. The high conductivity of the carbonized polyacrylamide submicron particles is used to make up for the insufficient conductivity of the composite oxide of TiO2 and CeO2, so that the composite oxide of TiO2 and CeO2 can have excellent electrochemical catalytic removal performance under a weak DC voltage. In order to enable the composite oxide of TiO2 and CeO2 to grow and coat on the surface of the carbonized polyacrylamide submicron particles to form submicron spheres, the surface of the carbonized polyacrylamide submicron particles is treated by plasma to increase the surface hydroxyl concentration. Using tetrabutyl titanate / tetraethyl titanate will slowly hydrolyze when contacting with moisture in the air, so that it can grow uniformly on the surface of the surface-modified carbonized polyacrylamide submicron particles. Finally, the titanium salt and cerium salt are converted into oxides by hydrothermal reaction and grown on the surface of the surface-modified carbonized polyacrylamide submicron particles to form composite submicron spheres. To avoid the aggregation of the composite submicron spheres, which will cause a decline in the electrochemical catalytic performance, they are printed on the paper surface by laser printing method, and then the paper is converted into a sheet-like carbon material by high-temperature carbonization. Finally, the carbonized polyacrylamide submicron particles wrapped by the composite oxide of TiO2 and CeO2 are uniformly dispersed on the surface of the sheet-like carbon material, that is, the nanoarray material. This nanoarray material not only has the high conductivity of carbon spheres but also has the excellent redox performance of titanium-cerium composite oxides. At the same time, nanochannels will be formed when the oxides grow on the surface of the carbon spheres. Therefore, it can have excellent adsorption, activation, and conversion performance during the DC electrocatalytic removal of chloride ions.

[0031] The second aspect of this application provides a method for preparing the nanoarray material provided in the first aspect of this application. The method includes:

[0032] S10: Prepare carbonized polyacrylamide submicron particles

[0033] Weigh acrylamide and dissolve it in deionized water. Add polyvinyl alcohol and stir to disperse to form a slurry, then heat it in a water bath. After reaching the reaction temperature of the water bath, add an initiator and continue stirring until the polymerization reaction ends. After the reaction ends, filter and vacuum dry to obtain polyacrylamide powder. Then place the polyacrylamide powder in a tubular reaction furnace, introduce nitrogen and heat it for carbonization to obtain carbonized polyacrylamide submicron particles. Finally, place the carbonized polyacrylamide submicron particles in a plasma surface treatment instrument. First, evacuate the plasma surface treatment instrument, then fill it with oxygen, and then perform surface treatment to obtain surface-modified carbonized polyacrylamide submicron particles;

[0034] S20: Load chloride ion remover

[0035] Weigh a titanium salt and dissolve it in ethanol, then add the surface-modified carbonized polyacrylamide submicron particles to obtain a mixed slurry. The mixed slurry is continuously stirred and exposed to air. After the hydrolysis of the titanium salt is complete, add a cerium salt and deionized water, and place it in a hydrothermal reaction kettle for hydrothermal reaction. After the hydrothermal reaction ends, filter and then vacuum dry to obtain a mixed particle powder;

[0036] S30: Prepare nanoarray material

[0037] Weigh the mixed particle powder and fill it into a toner cartridge. Then place the paper in a laser printer, start the laser printer for printing. After the mixed particle powder is printed on the paper, place the printed paper in a tubular reaction furnace, introduce nitrogen and heat it for carbonization. Finally, obtain the nanoarray material.

[0038] The method for preparing the nanoarray material proposed in this application uses acrylamide suspension polymerization to make polyacrylamide powder and then high-temperature carbonize it into carbonized polyacrylamide submicron particles. Utilize the high conductivity of the carbonized polyacrylamide submicron particles to make up for the insufficient conductivity of the composite oxide, so that the composite oxide of TiO2 and CeO2 can have excellent electrochemical catalytic removal performance under a weak DC voltage. Use plasma to treat the surface of the carbonized polyacrylamide submicron particles to increase the surface hydroxyl concentration. Finally, use hydrothermal reaction to convert the titanium salt and cerium salt into oxides and grow on the surface of the surface-modified carbonized polyacrylamide submicron particles to form composite submicron spheres; to avoid the aggregation of the composite submicron spheres resulting in a decline in electrochemical catalytic performance, use the laser printing method to print it on the paper surface, and then use high-temperature carbonization to convert the paper into a sheet-like carbon material. Finally, obtain the carbonized polyacrylamide submicron particles wrapped by the composite oxide of TiO2 and CeO2 evenly dispersed on the surface of the sheet-like carbon material, that is, the nanoarray material.

[0039] The following details each step of the method, referring to Figure 1 , the method includes:

[0040] S10: Prepare submicron particles of carbonized polyacrylamide

[0041] Weigh acrylamide and dissolve it in deionized water. Add polyvinyl alcohol and stir to disperse to form a slurry, then heat it in a water bath. After reaching the reaction temperature of the water bath, add an initiator and continue stirring until the polymerization reaction ends. After the reaction ends, filter and vacuum dry to obtain polyacrylamide powder. Then place the polyacrylamide powder in a tube furnace, introduce nitrogen and heat it to carbonize, obtaining submicron particles of carbonized polyacrylamide. Finally, place the submicron particles of carbonized polyacrylamide in a plasma surface treatment instrument. First, evacuate the plasma surface treatment instrument, then fill it with oxygen, and then perform surface treatment to obtain surface-modified submicron particles of carbonized polyacrylamide.

[0042] According to some embodiments of the present application, the initiator includes potassium persulfate or sodium persulfate, and the mass ratio of acrylamide, deionized water, polyvinyl alcohol, and the initiator is 1:(10 - 20):(0.005 - 0.010):(0.001 - 0.005).

[0043] As an example, the mass ratio of acrylamide, deionized water, polyvinyl alcohol, and the initiator can be 1:10:0.005:0.001, 1:15:0.01:0.003, 1:20:0.01:0.005, etc., or can be a range composed of any of the above values.

[0044] According to some embodiments of the present application, the molecular weight of the polyacrylamide is 200,000 - 800,000.

[0045] According to some embodiments of the present application, the temperature of the water bath heating is 50°C - 80°C, and the time of the water bath heating is 6h - 12h.

[0046] As an example, the temperature of the water bath heating can be 50°C, 60°C, 70°C, 80°C, etc., or can be a range composed of any of the above values.

[0047] As an example, the time of the water bath heating can be 6h, 8h, 10h, 12h, etc., or can be a range composed of any of the above values.

[0048] According to some embodiments of the present application, the temperature of the vacuum drying is 30°C - 60°C, the vacuum degree of the vacuum drying is 0.090MPa - 0.095MPa, and the time of the vacuum drying is 12h - 24h.

[0049] As an example, the temperature of the vacuum drying can be 30°C, 40°C, 50°C, 60°C, etc., or can be a range composed of any of the above values.

[0050] As an example, the time for vacuum drying can be 12h, 16h, 20h, 24h, etc., or can be a range composed of any of the above values.

[0051] According to some embodiments of the present application, the rate of nitrogen introduction is 30 mL / min - 60 mL / min. For example, it can be 30 mL / min, 40 mL / min, 50 mL / min, 60 mL / min, etc., or can be a range composed of any of the above values.

[0052] According to some embodiments of the present application, the temperature for heating and carbonizing is 600°C - 800°C, and the time for heating and carbonizing is 6h - 12h.

[0053] As an example, the temperature for heating and carbonizing can be 600°C, 650°C, 700°C, 750°C, etc., or can be a range composed of any of the above values.

[0054] As an example, the time for heating and carbonizing can be 6h, 8h, 10h, 12h, etc., or can be a range composed of any of the above values.

[0055] According to some embodiments of the present application, the plasma surface treatment instrument is of the Plasma clean - PL–5010 type.

[0056] The voltage for the surface treatment is 220V, and the working distance is 5mm - 10mm.

[0057] According to some embodiments of the present application, the scanning rate of the plasma flame during the surface treatment is 20mm / s - 40mm / s. For example, it can be 20mm / s, 30mm / s, 40mm / s, etc., or can be a range composed of any of the above values.

[0058] According to some embodiments of the present application, the volume ratio of oxygen to the carbonized polyacrylamide submicron particles is 1:(30 - 60). For example, it can be 1:30, 1:40, 1:50, 1:60, etc., or can be a range composed of any of the above values.

[0059] S20: Loading chloride ion remover

[0060] Weigh the titanium salt and dissolve it in ethanol, then add the surface - modified carbonized polyacrylamide submicron particles to obtain a mixed slurry. The mixed slurry is continuously stirred and exposed to air. After the titanium salt is completely hydrolyzed, add the cerium salt and deionized water, and place it in a hydrothermal reaction kettle for hydrothermal reaction. After the hydrothermal reaction is completed, filter and then vacuum - dry to obtain the mixed particle powder.

[0061] According to some embodiments of the present application, the titanium salt includes tetrabutyl titanate or tetraethyl titanate.

[0062] According to some embodiments of the present application, the mass ratio of the titanium salt to the ethanol is 1:(30 - 60), and the stirring rate is 100 r / min - 200 r / min.

[0063] As an example, the mass ratio of the titanium salt to the ethanol can be 1:30, 1:40, 1:50, 1:60, etc., or can be a range composed of any of the above values, so that the titanium salt is fully dissolved.

[0064] As an example, the stirring rate can be 100 r / min, 140 r / min, 155 r / min, 180 r / min, 200 r / min, etc., or can be a range composed of any of the above values, so that the titanium salt is fully dissolved.

[0065] According to some embodiments of the present application, the cerium salt includes cerium nitrate hexahydrate or cerium chloride hexahydrate, and the mass ratio of the cerium salt to the deionized water is 1:(60 - 100).

[0066] According to some embodiments of the present application, the temperature of the hydrothermal reaction is 140°C - 160°C, and the time of the hydrothermal reaction is 4 h - 8 h.

[0067] As an example, the temperature of the hydrothermal reaction can be 140°C, 145°C, 150°C, 155°C, 160°C, etc., or can be a range composed of any of the above values.

[0068] As an example, the time of the hydrothermal reaction can be 4 h, 6 h, 8 h, etc., or can be a range composed of any of the above values.

[0069] According to some embodiments of the present application, the temperature of the vacuum drying is 30°C - 60°C, the vacuum degree of the vacuum drying is 0.090 MPa - 0.095 MPa, and the time of the vacuum drying is 12 h - 24 h.

[0070] As an example, the temperature of the vacuum drying can be 30°C, 40°C, 50°C, 60°C, etc., or can be a range composed of any of the above values.

[0071] As an example, the time of the vacuum drying can be 12 h, 16 h, 20 h, 24 h, etc., or can be a range composed of any of the above values.

[0072] S30: Prepare the nanoarray material

[0073] Weigh the mixed particle powder and fill it into the toner cartridge, then place the paper in the laser printer, start the laser printer for printing. After the mixed particle powder is printed on the paper, place the printed paper in a tubular reaction furnace, introduce nitrogen and heat it up for carbonization, and finally obtain the nanoarray material.

[0074] According to some embodiments of the present application, the rate of introducing nitrogen is 30 mL / min - 60 mL / min. For example, it can be 30 mL / min, 40 mL / min, 50 mL / min, 60 mL / min, etc., or it can be a range composed of any of the above values.

[0075] According to some embodiments of the present application, the temperature for heating and carbonizing is 600 °C - 800 °C, and the time for heating and carbonizing is 6 h - 12 h.

[0076] As an example, the temperature for heating and carbonizing can be 600 °C, 650 °C, 700 °C, 750 °C, etc., or it can be a range composed of any of the above values.

[0077] As an example, the time for heating and carbonizing can be 6 h, 8 h, 10 h, 12 h, etc., or it can be a range composed of any of the above values.

[0078] The third aspect of the present application provides the application of the nanoarray material provided in the first aspect of the present application in removing chloride ions in the circulating water of coal-fired power plants.

[0079] The embodiments of the present application are described in detail below. The embodiments described below are exemplary and are only used to explain the present application and should not be construed as a limitation to the present application. For those techniques or conditions not specified in the embodiments, they shall be carried out according to the techniques or conditions described in the literature in the art or according to the product specifications. For reagents or instruments not specified by the manufacturer, they are all conventional products that can be obtained through commercial procurement.

[0080] Example 1

[0081] S10: Prepare carbonized polyacrylamide submicron particles

[0082] Weigh 100 g of acrylamide and dissolve it in 1000 g of deionized water. Add 0.5 g of polyvinyl alcohol and stir to disperse to form a slurry, then heat it in a water bath at 50 °C. After reaching the reaction temperature of the water bath heating, add 0.1 g of potassium persulfate, and continue stirring for 12 h until the polymerization reaction ends (maintain the water bath temperature at 50 °C during the stirring process). After the reaction ends, filter and vacuum dry at 30 °C for 24 h (the vacuum degree of drying is 0.090 MPa) to obtain polyacrylamide powder. Then place the polyacrylamide powder in a tubular reaction furnace, introduce nitrogen (the rate of nitrogen is 30 mL / min), and heat it to 600 °C for carbonization for 12 h to obtain carbonized polyacrylamide submicron particles. Finally, measure 30 mL of the carbonized polyacrylamide submicron particles and place them in a plasma surface treatment instrument. First, evacuate the plasma surface treatment instrument, then fill it with 1 mL of oxygen, and then under the conditions of an input voltage of 220 V, a working distance of 5 mm, and a plasma flame scanning rate of 20 mm / s, perform surface treatment on the carbonized polyacrylamide to obtain surface-modified carbonized polyacrylamide submicron particles. Repeat the surface modification step until the carbonized polyacrylamide particles are used up.

[0083] S20: Loading chloride adsorbent

[0084] Weigh 8.522 g of tetrabutyl titanate and dissolve it in 255.660 g of ethanol, then add 5 g of surface-modified carbonized polyacrylamide submicron particles to obtain a mixed slurry. The mixed slurry is continuously stirred at a rate of 100 r / min and exposed to air. After the hydrolysis of tetrabutyl titanate is complete, add 2.523 g of cerium nitrate hexahydrate and 151.380 g of deionized water, and place it in a hydrothermal reaction kettle for hydrothermal reaction at 140 °C for 8 h. After the hydrothermal reaction ends, filter, and then vacuum dry at 30 °C for 24 h (the vacuum degree of drying is 0.090 MPa) to obtain mixed particle powder. Repeat the cyclic step S20 until the surface-modified carbonized polyacrylamide submicron particles obtained in step S10 are used up.

[0085] S30: Preparation of nanoarray material

[0086] Weigh 50 g of the mixed particle powder prepared in step S20 and fill it into the toner cartridge. Then place a single A4 paper (4.99 g) in a laser printer, start the laser printer for printing. After 0.100 g of the mixed particle powder is evenly printed on the paper, place the printed paper in a tubular reaction furnace, introduce nitrogen (the rate of nitrogen is 30 mL / min), and heat it to 600 °C for carbonization for 12 h (the ablation residue of the A4 paper carbonized at this temperature to obtain carbonized paper is 25%). Finally, obtain the nanoarray material. Based on the mass of the carbonized paper substrate, the mass percentage content of the core is 5%, and the mass percentage content of the chloride remover is 3%. Among them, the mass ratio of TiO2 and CeO2 in the chloride remover is 1:0.5. The FE-SEM image of the nanoarray material is asFigure 2 and Figure 3 as shown

[0087] Example 2

[0088] S10: Prepare carbonized polyacrylamide submicron particles

[0089] Weigh 100 g of acrylamide and dissolve it in 2000 g of deionized water. Add 1 g of polyvinyl alcohol and stir to disperse to form a slurry, then heat it in a water bath at 80 °C. After reaching the reaction temperature of the water bath heating, add 0.5 g of sodium persulfate, and continue to stir for 6 h until the polymerization reaction ends (maintain the water bath temperature at 80 °C during the stirring process). After the reaction ends, filter and vacuum dry at 60 °C for 12 h (the vacuum degree of drying is 0.095 MPa) to obtain polyacrylamide powder. Then place the polyacrylamide powder in a tubular reaction furnace, introduce nitrogen (the rate of nitrogen is 60 mL / min), and heat it to 800 °C for carbonization for 6 h to obtain carbonized polyacrylamide submicron particles. Finally, measure 30 mL of carbonized polyacrylamide submicron particles and place them in a plasma surface treatment instrument. First, evacuate the plasma surface treatment instrument, then fill it with 0.5 mL of oxygen, and then perform surface treatment on the carbonized polyacrylamide under the conditions of an input voltage of 220 V, a working distance of 10 mm, and a plasma flame scanning rate of 40 mm / s to obtain surface-modified carbonized polyacrylamide submicron particles. Repeat the surface modification step until all the carbonized polyacrylamide particles are used up.

[0090] S20: Load chloride ion remover

[0091] Weigh 3.570 g of tetraethyl titanate and dissolve it in 214.200 g of ethanol, then add 5 g of surface-modified carbonized polyacrylamide submicron particles to obtain a mixed slurry. The mixed slurry is continuously stirred at a rate of 200 r / min and exposed to air. After the hydrolysis of tetraethyl titanate is complete, add 1.921 g of cerium chloride hexahydrate and 192.100 g of deionized water, and place it in a hydrothermal reaction kettle for hydrothermal reaction at 160 °C for 4 h. After the hydrothermal reaction ends, filter and then vacuum dry at 60 °C for 12 h (the vacuum degree of drying is 0.095 MPa) to obtain a mixed particle powder. Repeat the cyclic step S20 until all the surface-modified carbonized polyacrylamide submicron particles obtained in step S10 are used up.

[0092] S30: Prepare nanoarray materials

[0093] Weigh 50 g of the mixed particle powder prepared in step S20 and fill it into the toner cartridge. Then place a single A4 paper (4.99 g) in the laser printer, start the laser printer for printing. After 0.120 g of the mixed particle powder is evenly printed on the paper, place the printed paper in a tubular reaction furnace, introduce nitrogen (the rate of nitrogen is 60 mL / min), and heat it to 800 °C for carbonization for 6 h (at this temperature, the ablation residue of the A4 paper after carbonization to obtain carbonized paper is 20%). Finally, a nanoarray material is obtained. Based on the mass of the carbonized paper substrate, the mass percentage content of the core is 8%, and the mass percentage content of the chloride ion remover is 4%. Among them, the mass ratio of TiO2 and CeO2 in the chloride ion remover is 1:1. Performance test

[0094] Use conductive glue to stick the nanoarray material (1 g) to a stainless steel plate (1 cm × 1 cm) to form the positive electrode, and a carbon felt (1 cm × 1 cm) as the negative electrode. Use 100 mL of a calcium chloride solution with a concentration of 20 mmol / L as the circulating water simulation solution. After the nanoarray material reacts for 30 min at a DC voltage of 4.6 V, measure the concentration of chloride ions in the circulating water. The chloride ion removal rates of Example 1 and Example 2 are 92.6% and 94.8% respectively.

[0095] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0096] Although the embodiments of this application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting this application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A nanoarray material for removing chloride ions from circulating water in a coal-fired power plant by electrochemical means, characterized in that: The nano-array material is prepared by a suspension polymerization-high temperature carbonization-hydrothermal reaction-laser printing method using plasma-treated carbonized polyacrylamide submicron particles as the core, a composite oxide of TiO2 and CeO2 as the chloride ion remover, and carbonized paper as the substrate. The printed paper is placed in a tubular reactor, nitrogen is introduced, and the temperature is increased for carbonization to finally obtain the nano-array material, wherein the composite oxide of TiO2 and CeO2 wraps the carbonized polyacrylamide particles; Based on the mass of the carbonized paper, the mass percentage of the inner core is 5%-8%, and the mass percentage of the chloride ion remover is 3%-4%, wherein the mass ratio of the TiO2 to the CeO2 in the chloride ion remover is 1:(0.5-1).

2. A method for preparing the nanoarray material according to claim 1, characterized in that: include: S10: Preparation of Carbonized Polyacrylamide Submicron Particles Weigh acrylamide and dissolve it in deionized water, add polyvinyl alcohol, stir and disperse to form a slurry, and then heat it in a water bath. After reaching the water bath heating reaction temperature, add an initiator, continue stirring until the polymerization reaction is completed, filter and vacuum dry after the reaction is completed to obtain polyacrylamide powder, then place the polyacrylamide powder in a tubular reactor, introduce nitrogen and heat it to carbonize it to obtain carbonized polyacrylamide submicron particles, finally place the carbonized polyacrylamide submicron particles in a plasma surface treatment instrument, first evacuate the plasma surface treatment instrument, then fill it with oxygen, and then perform surface treatment to obtain surface-modified carbonized polyacrylamide submicron particles; S20: Loaded chloride ion remover Weigh titanium salt and dissolve it in ethanol, then add the surface-modified carbonized polyacrylamide submicron particles to obtain a mixed slurry, continuously stir the mixed slurry and expose it to air, add cerium salt and deionized water after the titanium salt is completely hydrolyzed, and place it in a hydrothermal reactor for hydrothermal reaction, filter it after the hydrothermal reaction is completed, and then vacuum dry it to obtain a mixed particle powder; S30: Preparation of nanoarray materials The mixed particle powder is weighed and filled into a toner cartridge, and then a paper is placed in a laser printer, and the laser printer is started to print. After the mixed particle powder is printed on the paper, the printed paper is placed in a tubular reactor, nitrogen is introduced, and the temperature is increased for carbonization, and finally the nanoarray material is obtained.

3. The method according to claim 2, characterized in that The initiator includes potassium persulfate or sodium persulfate, and the mass ratio of the acrylamide, the deionized water, the polyvinyl alcohol, and the initiator is 1: (10-20): (0.005-0.010): (0.001-0.005).

4. The method according to claim 2, characterized in that: In step S10, the water bath heating temperature is 50°C-80°C, the water bath heating time is 6h-12h, the vacuum drying temperature is 30°C-60°C, the vacuum degree of the vacuum drying is 0.090MPa-0.095MPa, and the vacuum drying time is 12h-24h.

5. The method according to claim 2, characterized in that: The rate of introducing nitrogen is 30 mL / min-60 mL / min, the temperature of heating carbonization is 600° C.-800° C., and the time of heating carbonization is 6 h-12 h.

6. The method according to claim 2, characterized in that During the plasma treatment, the plasma flame scanning rate is 20 mm / s-40 mm / s, and the volume ratio of the oxygen to the carbonized polyacrylamide submicron particles is 1:(30-60).

7. The method according to claim 2, characterized in that The titanium salt includes tetrabutyl titanate or tetraethyl titanate, the mass ratio of the titanium salt to the ethanol is 1:(30-60), and the stirring rate is 100r / min-200r / min.

8. The method according to claim 2, characterized in that: The cerium salt includes cerium nitrate hexahydrate or cerium chloride hexahydrate, and the mass ratio of the cerium salt to the deionized water is 1: (60-100).

9. The method according to claim 2, characterized in that: In step S20, the temperature of the hydrothermal reaction is 140°C-160°C, the time of the hydrothermal reaction is 4h-8h, the temperature of the vacuum drying is 30°C-60°C, the vacuum degree of the vacuum drying is 0.090MPa-0.095MPa, and the time of the vacuum drying is 12h-24h.

10. Use of the nanoarray material according to claim 1 in removing chloride ions from circulating water of a coal-fired power plant.

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