A composite macroporous adsorption resin pellet and its preparation method

Abstract

This invention discloses a composite macroporous adsorption resin sphere and its preparation method, comprising activated carbon spheres, wherein the activated carbon spheres have a metal oxide catalyst loaded on their outer surface, and the outer surface of the activated carbon spheres is constructed with a highly cross-linked macroporous adsorption resin layer. Beneficial effects: Using activated carbon spheres loaded with metal oxide catalysts as the core, low-crosslinked polystyrene spheres are constructed on the surface of the activated carbon spheres through multiple suspension polymerization methods. Finally, a styrene-divinyl composite sphere is formed using a swelling method and a post-crosslinking process. This composite sphere not only possesses the advantages of highly cross-linked macroporous resins—porous structure, high strength, and high adsorption performance—but also exhibits the characteristics of electrocatalytic oxidation of three-dimensional electrode particles. Under electrocatalytic oxidation, the strong oxidizing substances generated on the surface of the activated carbon particles, which act as three-dimensional electrode particles, have the highest concentration at the contact surface between the activated carbon and the resin. In particular, the generated hydroxyl radicals can directly oxidize organic matter adsorbed deep within the resin pores.

Description

Technical Field

[0001] This invention relates to the field of organic adsorption materials and electrode particle materials, and more specifically, to a composite macroporous adsorption resin pellet and its preparation method. Background Technology

[0002] Adsorption methods for treating organic waste gas and wastewater have been widely applied in production and daily life. Existing adsorption materials include activated carbon, bentonite, adsorption resins, and porous ceramic materials. Building upon this foundation, to improve adsorption efficiency, increase adsorption capacity, enhance the strength of adsorption materials, and improve adsorption stability, techniques such as activation, loading, oxidation, reduction, and cross-linking are used to modify the surface of these adsorption materials, promoting further development of adsorption materials.

[0003] With the advancements in polymer materials science in recent years, resin adsorption materials have been increasingly widely used.

[0004] Adsorption is divided into physical adsorption and chemical adsorption. When it comes to the adsorption of complex organic matter in industrial wastewater, both adsorption processes exist to varying degrees.

[0005] Specific surface area is one of the important parameters of adsorbents. For the same contact area, the more and smaller the pore size, the larger the specific surface area; conversely, the larger the pore size and the fewer the number of pores, the smaller the specific surface area. To increase the specific surface area of ​​macroporous resins, researchers have studied various technical solutions, among which post-crosslinking is one of the representative methods. Macroporous resins prepared using the post-crosslinking method significantly improve the degree of crosslinking, increasing the surface area of ​​the macroporous adsorption resin from 300 m² / g to 1000-1500 m² / g, resulting in higher adsorption capacity.

[0006] However, adsorption resins with small pore size and a large number of pores and large specific surface area are limited in practical applications due to the difficulty in removing adsorbed organic matter, especially organic matter adsorbed deep in the pores.

[0007] The desorption of organic matter from resin, also known as resin regeneration, requires the removal of organic matter adsorbed by the adsorbent material. The desorbed adsorbent resin can be recycled, and multiple adsorption / desorption processes can effectively reduce operating costs.

[0008] For general macroporous adsorption resins, desorption can be achieved through chemical methods, organic solvent extraction, thermal methods, etc.

[0009] Chemical methods typically use acid or alkali solutions to react chemically with the adsorbed organic matter, thereby regenerating the resin. For example, in the adsorption process of wastewater from methyl salicylate production, an 8% concentration of sodium hydroxide is used for desorption. The high-concentration desorption solution is then acidified, concentrated, and cooled to crystallize 5-sulfosalicylic acid.

[0010] Organic solvent extraction methods, such as resin adsorption processes for treating wastewater from nitrobenzene and nitrochlorobenzene production, use isopropanol as a desorbent. High-concentration desorbed solutions require distillation to recover isopropanol and nitrobenzene.

[0011] Thermal method: Desorption is carried out using high-temperature hot water, but the desorption efficiency of hot water is limited. To improve the desorption efficiency, high-temperature steam can be used for purging to desorb volatile organic compounds, which are then separated and processed again.

[0012] For highly cross-linked macroporous adsorption resins, due to their relatively small surface pore size, they have a stronger adsorption capacity. Moreover, the adsorbed organic matter exists inside the pores. Acid-base methods, organic solvent extraction methods, thermal methods, etc., can only desorb organic matter on the surface or in the middle of the pores, and cannot desorb organic matter inside the pores.

[0013] Electrochemical technology has unique advantages in the removal of organic matter, among which electrocatalytic oxidation technology is the most representative. Electrocatalytic oxidation relies on the electrocatalytic function of the main electrode or three-dimensional electrode particles to generate strong oxidizing substances such as hydroxyl radicals, H2O2, and O3 in aqueous solution, mineralizing organic matter into water and carbon dioxide. It is an environmentally friendly organic matter removal technology. However, the high cost of electrodes and the high energy consumption of electrocatalytic oxidation are constraints that limit the widespread application of this technology.

[0014] The three-dimensional electrocatalytic oxidation device, which uses activated carbon particles to support catalysts as three-dimensional electrode particles, improves the current efficiency of traditional plate-type electrocatalytic oxidation units and reduces the energy consumption of the electrocatalytic oxidation process, thus opening up new directions for electrochemical technology in the adsorption and treatment of organic matter.

[0015] However, electrocatalytic oxidation technology has not yet seen practical applications on macroporous adsorption resins. This is mainly because the most potent oxidizing hydroxyl radicals generated at the electrocatalytic oxidation electrode have an extremely short lifespan in water, lasting only 10⁻⁹ s in the liquid phase. Therefore, they can only oxidize organic matter near the electrode. Conventional macroporous adsorption resin particles are small and mostly insulators, lacking the characteristics of electrode particles. To achieve desorption using electrocatalysis, three-dimensional electrocatalytic oxidation particles need to be placed around the adsorption resin particles. The electrode particles contact the resin particle surface, and under the influence of an electric field, the strong oxides generated on the electrode particle surface oxidize and remove organic matter from the contacted resin particle surface. However, this process fails to remove organic matter inside the resin pores.

[0016] To address the difficulty in desorbing organic matter after adsorption by highly cross-linked macroporous adsorption resins, a composite macroporous adsorption resin with electrode particle characteristics is needed:

[0017] 1. It has the adsorption advantages of highly cross-linked macroporous resin, such as numerous micropores, large specific surface area, and large adsorption capacity;

[0018] 2. The regeneration process after adsorption can remove organic matter deep in the pores, so that the resin is completely regenerated without affecting the adsorption performance after regeneration.

[0019] 3. The regeneration process can be combined with the desorption process of general macroporous resins, including acid-base method, thermal method, etc., and the best regeneration solution can be sought through a comprehensive evaluation of economic and environmental benefits.

[0020] No effective solutions have yet been proposed to address the problems in the relevant technologies. Summary of the Invention

[0021] To address the problems in related technologies, this invention proposes a composite macroporous adsorption resin sphere and its preparation method to overcome the aforementioned technical problems existing in the prior art.

[0022] Therefore, the specific technical solution adopted by the present invention is as follows:

[0023] A composite macroporous adsorption resin pellet includes activated carbon pellets, wherein the activated carbon pellets have a metal oxide catalyst loaded on their outer surface, and the outer surface of the activated carbon pellets is constructed with a highly cross-linked macroporous adsorption resin layer.

[0024] Preferably, the activated carbon particles have a spherical structure and a diameter of 3 mm.

[0025] Preferably, the thickness of the highly cross-linked macroporous adsorption resin layer is 0.5-1 mm.

[0026] According to another aspect of the present invention, a method for preparing composite macroporous adsorption resin spheres is provided, wherein the specific preparation steps of the activated carbon spheres are as follows:

[0027] A. Select wood-based or coal-based charcoal for preliminary carbonization;

[0028] B. Crush, sieve, and granulate the carbonized activated carbon;

[0029] C. After drying the activated carbon granules, carbonize them in a carbonization furnace;

[0030] D. Load the activated carbon particles obtained in step C with a titanium oxide catalyst.

[0031] According to another aspect of the present invention, a method for preparing composite macroporous adsorption resin spheres is provided, wherein the specific steps of the method for preparing the composite macroporous adsorption resin spheres are as follows:

[0032] A. Place activated carbon granules in styrene for impregnation and adsorption;

[0033] B. A cross-linked macroporous adsorption resin membrane is formed on the surface of activated carbon particles using a suspension polymerization method;

[0034] C. Repeat steps A and B multiple times until a resin layer with a thickness of 0.5-1mm is formed on the surface of the activated carbon pellets;

[0035] D. The resin spheres obtained in step C are swollen, and adsorption resin spheres are constructed using a post-crosslinking method.

[0036] The beneficial effects of this invention are as follows:

[0037] This invention uses activated carbon spheres loaded with metal oxide catalysts as the core. A multiple suspension polymerization method is employed to construct low-crosslinked polystyrene spheres on the surface of the activated carbon spheres. Finally, a swelling method and post-crosslinking are used to form styrene-divinyl composite spheres. These composite spheres not only possess the advantages of highly crosslinked macroporous resins—porous structure, high strength, and high adsorption capacity—but also exhibit the characteristics of electrocatalytic oxidation of three-dimensional electrode particles. Furthermore, the deep pores of the macroporous resin are directly connected to the surface of the activated carbon spheres. Under electrocatalytic oxidation, the strong oxidizing substances generated on the surface of the activated carbon particles (acting as three-dimensional electrode particles) reach the highest concentration at the interface between the activated carbon and the resin. In particular, the generated hydroxyl radicals can directly oxidize the organic matter adsorbed deep within the resin pores. This solves the problem of difficult removal of deep-pore organic matter during the regeneration process of existing highly crosslinked macroporous adsorption resins.

[0038] This invention combines the advantages of highly cross-linked adsorption resin adsorption with the desorption advantages of activated carbon particles loaded with catalysts. The resin adsorption layer is coated on the activated carbon electrode particles, which can prevent the formation of short-circuit current during the electrocatalytic oxidation of activated carbon particles. The resin coating also avoids the corrosion and detachment failure of metal oxides loaded on activated carbon, thus extending the service life of the composite macroporous adsorption resin particles with electrode particle characteristics.

[0039] With the rational design of the power supply and electrodes, this invention can realize in-situ regeneration of resin adsorption by electrocatalytic oxidation; combined with acid-base desorption, it can improve the desorption efficiency to 100% crystallization; combined with resin thermal desorption and biological organic matter removal, it can realize green in-situ regeneration of adsorption resin with low energy consumption and no need for reagents.

[0040] The activated carbon core of this invention is activated at low temperature, has a small specific surface area, and exhibits good hydrophobicity, making it easier to adsorb styrene into an emulsion film layer in water. This facilitates the formation of an adsorption resin layer on the particle surface using suspension polymerization. The spheres formed by the activated carbon core are loaded with metal oxides, enabling them to function as three-dimensional electrode particles in electrolyte aqueous solutions under DC or high-frequency electric fields. The strongly oxidizing hydroxyl radicals formed on the particle surface can efficiently oxidize and remove organic matter near the particle electrode.

[0041] The highly cross-linked resin layer of this invention has more pores, a larger specific surface area, and stronger adsorption capacity. Simultaneously, it possesses electrode particle characteristics, utilizing strong oxides such as hydroxyl radicals formed on the surface of activated carbon spheres during electrocatalytic oxidation to mineralize and remove organic matter adsorbed deep within the pores and very close to the activated carbon surface. This solves the problem of difficulty in removing organic matter adsorbed deep within the resin pores during the regeneration of highly cross-linked resins, especially during the adsorption of complex organic matter, and can improve the resin regeneration efficiency to nearly 100%. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a schematic diagram of the structure of a composite macroporous adsorption resin pellet according to an embodiment of the present invention;

[0044] Figure 2 This is a flowchart illustrating the specific steps of the activated carbon core preparation method in a method for preparing composite macroporous adsorption resin pellets according to an embodiment of the present invention.

[0045] Figure 3 This is a flowchart illustrating the specific steps of a method for preparing a highly cross-linked macroporous adsorption resin layer in a method for preparing composite macroporous adsorption resin spheres according to an embodiment of the present invention.

[0046] In the picture:

[0047] 1. Highly cross-linked macroporous adsorption resin layer; 2. Activated carbon particles. Detailed Implementation

[0048] To further illustrate the various embodiments, the present invention provides accompanying drawings, which are part of the disclosure of the present invention. These drawings are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these drawings, those skilled in the art should be able to understand other possible implementation methods and the advantages of the present invention. The components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0049] According to embodiments of the present invention, a composite macroporous adsorption resin pellet and a method for preparing the same are provided. Example 1

[0050] like Figure 1As shown, the composite macroporous adsorption resin pellets according to an embodiment of the present invention include activated carbon pellets 2, wherein the activated carbon pellets 2 have a metal oxide catalyst loaded on their outer surface, and the outer surface of the activated carbon pellets 2 is constructed with a highly cross-linked macroporous adsorption resin layer 1.

[0051] The activated carbon particles 2 have a spherical structure and a diameter of 3 mm. The highly cross-linked macroporous adsorption resin layer 1 has a thickness of 0.5-1 mm. Example 2

[0052] like Figure 1-2 As shown in the embodiments of the present invention, a method for preparing composite macroporous adsorption resin spheres is also provided, for use in composite macroporous adsorption resin spheres, wherein the specific preparation steps of the activated carbon spheres 2 are as follows:

[0053] Step 1: Using wood, sawdust, and tree roots as raw materials, dehydrate them at 120 degrees Celsius, then pyrolyze them at 200 degrees Celsius, and finally carbonize them at 300 degrees Celsius.

[0054] Step 2: Crush the carbonized wood chips and sieve them into 100-mesh powder.

[0055] Step 3: Add an appropriate amount of water according to the weight ratio of carbonized sawdust: bentonite: attapulgite = 100: 5: 10 to meet the moisture requirements for granulation and molding, and stir evenly.

[0056] Step 4: Shape the pellets into 3mm spheres in a disc or drum granulator, and dry them at a low temperature until the moisture content is 30-40%.

[0057] Step 5: Carbonize the low-temperature dried activated carbon balls in a carbonization furnace at 300℃.

[0058] Step 6: Prepare a 5% (w / w) titanium sulfate aqueous solution and immerse the carbonized activated carbon balls in it for at least 0.5 hours.

[0059] Step 7: Reductive activation of activated carbon balls. Activation is performed using a carbonization furnace with inert gas at a temperature of 500 degrees Celsius for 3 hours.

[0060] Wood-based activated carbon, carbonized at low temperatures, is used because of its relatively low specific surface area. After carbonization, it exhibits high electrical conductivity and excellent hydrophobicity. Alternatively, sludge-based activated carbon or coal-based activated carbon with slightly larger specific surface areas can also be used.

[0061] By loading titanium dioxide catalysts, it can be effectively utilized because titanium dioxide is resistant to most water quality environments, including chlorine, acids, and alkalis, and exhibits excellent electrocatalytic generation of hydroxyl radicals. For wastewater containing special organic components or wastewater with special water quality environments, targeted electrocatalytic oxidation catalysts such as various transition metal oxides can also be selected for loading.

[0062] Activation with an inert gas is also intended to give the activated carbon balls higher hydrophobicity, which is beneficial for the adsorption and cross-linking of styrene emulsion on the surface of the balls during the suspension polymerization process. Example 3

[0063] like Figure 1-2 As shown in the embodiments of the present invention, a method for preparing composite macroporous adsorption resin spheres is also provided, for use in composite macroporous adsorption resin spheres, wherein the specific preparation steps of the activated carbon spheres 2 are as follows:

[0064] Step 1: Using wood, sawdust, and tree roots as raw materials, dehydrate them at 120 degrees Celsius, then pyrolyze them at 250 degrees Celsius, and finally carbonize them at 400 degrees Celsius.

[0065] Step 2: Crush the carbonized wood chips and sieve them into 150-mesh powder.

[0066] Step 3: Add an appropriate amount of water according to the weight ratio of carbonized sawdust: bentonite: attapulgite = 100: 5: 10 to meet the moisture requirements for granulation and molding, and stir evenly.

[0067] Step 4: Shape the pellets into 3mm spheres in a disc or drum granulator, and dry them at a low temperature until the moisture content is 30-40%.

[0068] Step 5: Carbonize the low-temperature dried activated carbon balls in a carbonization furnace at 400℃.

[0069] Step 6: Prepare a 5% (w / w) titanium sulfate aqueous solution and immerse the carbonized activated carbon balls in it for at least 0.5 hours.

[0070] Step 7: Reductive activation of activated carbon balls. Activation is performed using a carbonization furnace with inert gas at a temperature of 500 degrees Celsius for 3 hours.

[0071] Wood-based activated carbon, carbonized at low temperatures, is used because of its relatively low specific surface area. After carbonization, it exhibits high electrical conductivity and excellent hydrophobicity. Alternatively, sludge-based activated carbon or coal-based activated carbon with slightly larger specific surface areas can also be used.

[0072] By loading titanium dioxide catalysts, it can be effectively utilized because titanium dioxide is resistant to most water quality environments, including chlorine, acids, and alkalis, and exhibits excellent electrocatalytic generation of hydroxyl radicals. For wastewater containing special organic components or wastewater with special water quality environments, targeted electrocatalytic oxidation catalysts such as various transition metal oxides can also be selected for loading.

[0073] Activation with an inert gas is also intended to give the activated carbon balls higher hydrophobicity, which is beneficial for the adsorption and cross-linking of styrene emulsion on the surface of the balls during the suspension polymerization process. Example 4

[0074] like Figure 1-2 As shown in the embodiments of the present invention, a method for preparing composite macroporous adsorption resin spheres is also provided, for use in composite macroporous adsorption resin spheres, wherein the specific preparation steps of the activated carbon spheres 2 are as follows:

[0075] Step 1: Using wood, sawdust, and tree roots as raw materials, dehydrate them at 120 degrees Celsius, then pyrolyze them at 300 degrees Celsius, and finally carbonize them at 500 degrees Celsius.

[0076] Step 2: Crush the carbonized wood chips and sieve them into 200-mesh powder.

[0077] Step 3: Add an appropriate amount of water according to the weight ratio of carbonized sawdust: bentonite: attapulgite = 100: 5: 10 to meet the moisture requirements for granulation and molding, and stir evenly.

[0078] Step 4: Shape the pellets into 3mm spheres in a disc or drum granulator, and dry them at a low temperature until the moisture content is 30-40%.

[0079] Step 5: Carbonize the low-temperature dried activated carbon balls in a carbonization furnace at 500℃.

[0080] Step 6: Prepare a 5% (w / w) titanium sulfate aqueous solution and immerse the carbonized activated carbon balls in it for at least 0.5 hours.

[0081] Step 7: Reductive activation of activated carbon balls. Activation is performed using a carbonization furnace with inert gas at a temperature of 500 degrees Celsius for 3 hours.

[0082] Wood-based activated carbon, carbonized at low temperatures, is used because of its relatively low specific surface area. After carbonization, it exhibits high electrical conductivity and excellent hydrophobicity. Alternatively, sludge-based activated carbon or coal-based activated carbon with slightly larger specific surface areas can also be used.

[0083] By loading titanium dioxide catalysts, it can be effectively utilized because titanium dioxide is resistant to most water quality environments, including chlorine, acids, and alkalis, and exhibits excellent electrocatalytic generation of hydroxyl radicals. For wastewater containing special organic components or wastewater with special water quality environments, targeted electrocatalytic oxidation catalysts such as various transition metal oxides can also be selected for loading.

[0084] Activation with an inert gas is also intended to give the activated carbon balls higher hydrophobicity, which is beneficial for the adsorption and cross-linking of styrene emulsion on the surface of the balls during the suspension polymerization process. Example 5

[0085] like Figure 1 As shown in Figure 3, according to an embodiment of the present invention, a method for preparing composite macroporous adsorption resin spheres is also provided, for use in composite macroporous adsorption resin spheres. The specific preparation steps of the highly cross-linked macroporous adsorption resin layer 1 are as follows:

[0086] Step 1: Immerse the spherical activated carbon particles 2 in styrene solution and stir and mix at room temperature for 0.5 hours;

[0087] Step 2: Prepare a deionized water solution, add initiator and pore-forming agent to the deionized water, stir well, and heat the solution to 50°C;

[0088] Step 3: Add the spherical activated carbon particles 2, which are impregnated with styrene, to a solution at 50°C, and add an appropriate amount of divinylbenzene. Gradually raise the temperature to 90°C to carry out low-temperature suspension polymerization crosslinking and curing for 5 hours.

[0089] Step 4: Remove the granules that have initially cross-linked into polystyrene on the surface, cool them rapidly, and centrifuge to dry them;

[0090] Step 5: Repeat steps 1-4 several times with the cross-linked microspheres until the surface of the microspheres is covered with a low cross-linked resin layer with a thickness of 0.5 mm;

[0091] Step 6: Cool the material, then adjust the pH value to 4-6 by adding hydrochloric acid, and wash it. After washing, dehydrate it using a centrifuge. After dehydration and drying, polystyrene adsorption resin balls with an average particle size of 4 mm activated carbon core are obtained.

[0092] Step 7: Immerse the low cross-linked resin balls in a swelling agent, add nitrobenzene or dichloroethane, and allow them to swell for 12 hours;

[0093] Step 8: Using the seed ball swelling polymerization method, add a mixed solution containing styrene, divinylbenzene, toluene, photo-oxidized tolueneyl, and sodium dodecyl sulfate, add an appropriate amount of 5% polyvinyl alcohol solution, and heat to 70 degrees Celsius to react for 10 hours.

[0094] Step 9: The product is washed sequentially with water and ethanol, and then vacuum dried at 80 degrees Celsius for 12 hours to obtain styrene-divinyl spheres with a crosslinking degree greater than 60%.

[0095] The activated carbon core (spherical activated carbon particles 2) is hydrophobic and oleophilic, and can adsorb styrene monomers in its pores and on its surface. After adsorption, the styrene formed on the surface forms an emulsion film in water, and under the conditions of 90 degrees Celsius and initiator, porogen, and catalyst, it is initially crosslinked into a macroporous resin layer.

[0096] The adsorption resin layer formed by one cross-linking can be used to adsorb styrene monomers again to form a film. The process of immersing in the styrene monomer solution, adsorbing on the surface to form a film, and emulsifying and cross-linking can be repeated to thicken the resin layer to 0.5-1 mm.

[0097] The activated carbon core (spherical activated carbon particles 2) resin pre-crosslinked spheres were subjected to swelling polymerization. Nitrobenzene or dichloroethane was added for swelling for 12 hours. A mixed solution containing styrene, divinylbenzene, toluene, photo-oxidized tolueneyl, and sodium dodecyl sulfate was added. An appropriate amount of 5% polyvinyl alcohol solution was added, and the temperature was raised to 70 degrees and reacted for 10 hours to form a styrene-divinyl high crosslinked macroporous adsorption resin with a crosslinking degree greater than 60%. Example 6

[0098] like Figure 1 As shown in Figure 3, according to an embodiment of the present invention, a method for preparing composite macroporous adsorption resin spheres is also provided, for use in composite macroporous adsorption resin spheres. The specific preparation steps of the highly cross-linked macroporous adsorption resin layer 1 are as follows:

[0099] Step 1: Immerse the spherical activated carbon particles 2 in styrene solution and stir and mix at room temperature for 0.7 hours;

[0100] Step 2: Prepare a deionized water solution, add initiator and pore-forming agent to the deionized water, stir well, and heat the solution to 50°C;

[0101] Step 3: Add the spherical activated carbon particles 2, which are impregnated with styrene, to a solution at 50°C, and add an appropriate amount of divinylbenzene. Gradually raise the temperature to 90°C to carry out low-temperature suspension polymerization crosslinking and curing for 5 hours.

[0102] Step 4: Remove the granules that have initially cross-linked into polystyrene on the surface, cool them rapidly, and centrifuge to dry them;

[0103] Step 5: Repeat steps 1-4 several times after cross-linking the microspheres until the surface of the microspheres is covered with a low cross-linking resin layer with a thickness of 0.7 mm;

[0104] Step six: Cool the material, then adjust the pH value to 5 by adding hydrochloric acid, and wash it. After washing, dehydrate it using a centrifuge. After dehydration and drying, polystyrene adsorption resin balls with an average particle size of 4.5 mm activated carbon core are obtained.

[0105] Step 7: Immerse the low cross-linked resin balls in a swelling agent, add nitrobenzene or dichloroethane, and allow them to swell for 12 hours;

[0106] Step 8: Using the seed ball swelling polymerization method, add a mixed solution containing styrene, divinylbenzene, toluene, photo-oxidized tolueneyl, and sodium dodecyl sulfate, add an appropriate amount of 5% polyvinyl alcohol solution, and heat to 70 degrees Celsius to react for 10 hours.

[0107] Step 9: The product is washed sequentially with water and ethanol, and then vacuum dried at 80 degrees Celsius for 12 hours to obtain styrene-divinyl spheres with a crosslinking degree greater than 60%.

[0108] The activated carbon core (spherical activated carbon particles 2) is hydrophobic and oleophilic, and can adsorb styrene monomers in its pores and on its surface. After adsorption, the styrene formed on the surface forms an emulsion film in water, and under the conditions of 90 degrees Celsius and initiator, porogen, and catalyst, it is initially crosslinked into a macroporous resin layer.

[0109] The adsorption resin layer formed by one cross-linking can be used to adsorb styrene monomers again to form a film. The process of immersing in the styrene monomer solution, adsorbing on the surface to form a film, and emulsifying and cross-linking can be repeated to thicken the resin layer to 0.5-1 mm.

[0110] The activated carbon core (spherical activated carbon particles 2) resin pre-crosslinked spheres were subjected to swelling polymerization. Nitrobenzene or dichloroethane was added for swelling for 12 hours. A mixed solution containing styrene, divinylbenzene, toluene, photo-oxidized tolueneyl, and sodium dodecyl sulfate was added. An appropriate amount of 5% polyvinyl alcohol solution was added, and the temperature was raised to 70 degrees and reacted for 10 hours to form a styrene-divinyl high crosslinked macroporous adsorption resin with a crosslinking degree greater than 60%. Example 7

[0111] like Figure 1 As shown in Figure 3, according to an embodiment of the present invention, a method for preparing composite macroporous adsorption resin spheres is also provided, for use in composite macroporous adsorption resin spheres. The specific preparation steps of the highly cross-linked macroporous adsorption resin layer 1 are as follows:

[0112] Step 1: Immerse the spherical activated carbon particles 2 in styrene solution and stir and mix at room temperature for 1 hour;

[0113] Step 2: Prepare a deionized water solution, add initiator and pore-forming agent to the deionized water, stir well, and heat the solution to 50°C;

[0114] Step 3: Add the spherical activated carbon particles 2, which are impregnated with styrene, to a solution at 50°C, and add an appropriate amount of divinylbenzene. Gradually raise the temperature to 90°C to carry out low-temperature suspension polymerization crosslinking and curing for 5 hours.

[0115] Step 4: Remove the granules that have initially cross-linked into polystyrene on the surface, cool them rapidly, and centrifuge to dry them;

[0116] Step 5: Repeat steps 1-4 several times after cross-linking the microspheres until the surface of the microspheres is covered with a 1mm thick layer of low cross-linked resin.

[0117] Step 6: Cool the material, then adjust the pH value to 4-6 by adding hydrochloric acid, and wash it. After washing, dehydrate it using a centrifuge. After dehydration and drying, polystyrene adsorption resin balls with an average particle size of 5 mm activated carbon core are obtained.

[0118] Step 7: Immerse the low cross-linked resin balls in a swelling agent, add nitrobenzene or dichloroethane, and allow them to swell for 12 hours;

[0119] Step 8: Using the seed ball swelling polymerization method, add a mixed solution containing styrene, divinylbenzene, toluene, photo-oxidized tolueneyl, and sodium dodecyl sulfate, add an appropriate amount of 5% polyvinyl alcohol solution, and heat to 70 degrees Celsius to react for 10 hours.

[0120] Step 9: The product is washed sequentially with water and ethanol, and then vacuum dried at 80 degrees Celsius for 12 hours to obtain styrene-divinyl spheres with a crosslinking degree greater than 60%.

[0121] The activated carbon core (spherical activated carbon particles 2) is hydrophobic and oleophilic, and can adsorb styrene monomers in its pores and on its surface. After adsorption, the styrene formed on the surface forms an emulsion film in water, and under the conditions of 90 degrees Celsius and initiator, porogen, and catalyst, it is initially crosslinked into a macroporous resin layer.

[0122] The adsorption resin layer formed by one cross-linking can be used to adsorb styrene monomers again to form a film. The process of immersing in the styrene monomer solution, adsorbing on the surface to form a film, and emulsifying and cross-linking can be repeated to thicken the resin layer to 0.5-1 mm.

[0123] The activated carbon core (spherical activated carbon particles 2) resin pre-crosslinked spheres were subjected to swelling polymerization. Nitrobenzene or dichloroethane was added for swelling for 12 hours. A mixed solution containing styrene, divinylbenzene, toluene, photo-oxidized tolueneyl, and sodium dodecyl sulfate was added. An appropriate amount of 5% polyvinyl alcohol solution was added, and the temperature was raised to 70 degrees and reacted for 10 hours to form a styrene-divinyl high crosslinked macroporous adsorption resin with a crosslinking degree greater than 60%.

[0124] In summary, this invention uses activated carbon spheres loaded with metal oxide catalysts as the core, and employs a multiple suspension polymerization method to construct low-crosslinked polystyrene spheres on the surface of the activated carbon spheres. Finally, a swelling method and post-crosslinking are used to form styrene-divinyl composite spheres. These composite spheres not only possess the advantages of highly crosslinked macroporous resins—porous structure, high strength, and high adsorption capacity—but also exhibit the characteristics of electrocatalytic oxidation of three-dimensional electrode particles. Furthermore, the deep pores of the macroporous resin are directly connected to the surface of the activated carbon spheres. Under electrocatalytic oxidation, the strong oxidizing substances generated on the surface of the activated carbon particles (acting as three-dimensional electrode particles) reach the highest concentration at the interface between the activated carbon and the resin. In particular, the generated hydroxyl radicals can directly oxidize the organic matter adsorbed deep within the resin pores. This solves the problem of difficult removal of organic matter deep within the pores during the regeneration process of existing highly crosslinked macroporous adsorption resins.

[0125] This invention combines the advantages of highly cross-linked adsorption resin adsorption with the desorption advantages of activated carbon particles loaded with catalysts. The resin adsorption layer is coated on the activated carbon electrode particles, which can prevent the formation of short-circuit current during the electrocatalytic oxidation of activated carbon particles. The resin coating also avoids the corrosion and detachment failure of metal oxides loaded on activated carbon, thus extending the service life of the composite macroporous adsorption resin particles with electrode particle characteristics.

[0126] With the rational design of the power supply and electrodes, this invention can realize in-situ regeneration of resin adsorption by electrocatalytic oxidation; combined with acid-base desorption, it can improve the desorption efficiency to 100% crystallization; combined with resin thermal desorption and biological organic matter removal, it can realize green in-situ regeneration of adsorption resin with low energy consumption and no need for reagents.

[0127] The activated carbon core 2 of this invention is activated at low temperature, has a small specific surface area, and exhibits good hydrophobicity, making it easier to adsorb styrene into an emulsion film layer in water. This facilitates the formation of an adsorption resin layer on the particle surface using suspension polymerization. The spheres formed by the activated carbon core 2 are loaded with metal oxides, enabling them to function as three-dimensional electrode particles in electrolyte aqueous solutions under DC or high-frequency electric fields. The strong oxidizing hydroxyl radicals formed on the particle surface can efficiently oxidize and remove organic matter near the particle electrode.

[0128] The highly cross-linked resin layer 1 of this invention has more pores, a larger specific surface area, and stronger adsorption capacity. Simultaneously, it possesses electrode particle characteristics, utilizing strong oxides such as hydroxyl radicals formed on the surface of activated carbon spheres during electrocatalytic oxidation to mineralize and remove organic matter adsorbed deep within the pores and very close to the activated carbon surface. This solves the problem of difficulty in removing organic matter adsorbed deep within the resin pores during the regeneration process of highly cross-linked resins, especially during the adsorption of complex organic matter, and can improve the resin regeneration efficiency to nearly 100%.

[0129] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A composite macroporous adsorption resin granule, characterized in that, It includes activated carbon particles (2), wherein the activated carbon particles (2) have metal oxide catalysts loaded on their outer surface, and the outer surface of the activated carbon particles (2) is constructed with a highly cross-linked macroporous adsorption resin layer (1). The specific preparation method of the activated carbon particles (2) is as follows: A. Select wood-based or coal-based charcoal for preliminary carbonization; B. Crush, sieve, and granulate the carbonized activated carbon; C. After drying the activated carbon granules, carbonize them in a carbonization furnace; D. Load the activated carbon particles obtained in step C with a titanium oxide catalyst. The specific preparation steps of the composite macroporous adsorption resin spheres are as follows: A. Place activated carbon granules (2) in styrene for impregnation and adsorption; B. A cross-linked macroporous adsorption resin membrane is formed on the surface of activated carbon particles (2) by suspension polymerization. C. Repeat steps A and B repeatedly until a resin layer with a thickness of 0.5-1 mm is formed on the surface of the activated carbon particles (2); D. The resin spheres obtained in step C are swollen, and adsorption resin spheres are constructed using a post-crosslinking method. The activated carbon particles (2) have a spherical structure and a diameter of 3 mm.

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