Modified phenolic resin microspheres and their application in the preparation of carbon spheres and activated carbon spheres

Abstract

The invention discloses a modified phenolic resin microsphere and its application in preparing carbon balls and activated carbon balls, belonging to the field of chemical synthesis technology. The phenolic resin is modified by propanol to have the characteristics of complex linear curing, high strength, high temperature resistance, high ball rate, etc., and is used as a carbon source to prepare carbon balls through a carbonization furnace, and then the carbon balls are used as raw materials to be activated by water vapor at high temperature through an activation furnace to prepare activated carbon balls. The phenolic resin is modified by propanol, and the raw material source is rich; the modified phenolic resin obtained has high strength, high ball rate and high temperature resistance, and the ball rate is still above 90% and the strength is maintained above 40N after carbonization and activation; the impurity content in the carbon powder is small, and the porosity, pore volume, pore diameter and specific surface area after activation can meet the requirements of medical adsorbents, blood perfusion and energy storage and gas storage; synthetic materials are used as carbon sources, the impurity content is small, the waste gas, waste liquid and impurities generated are small, and they can be recycled after adsorption treatment.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical synthesis, and particularly relates to modified phenolic resin microspheres and applications of the microspheres in preparing carbon spheres and activated carbon spheres. Background Art

[0002] Phenolic resin (PF) has abundant raw material sources, low price, simple production process, excellent mechanical properties, heat resistance, electrical insulation, dimensional stability, molding processability and flame retardancy. The products have good dimensional stability, excellent electrical insulation performance and low smoke. It has become an indispensable material in the industrial sector and is widely used in related industries such as automobiles, home appliances, electronics and electrical, steel and housing. However, with the development of industry, especially the development of aerospace and other cutting-edge defense technologies, new requirements have been put forward for phenolic resin, and scientific researchers have also done a lot of research on the synthesis, modification and application of phenolic resin.

[0003] Spherical polymer materials have excellent chemical stability and high specific surface area. If phenolic resin is prepared into microspheres, it can not only give full play to its existing excellent properties, but also reflect the characteristics of polymer microspheres, thereby broadening the application field of phenolic resin, such as energy storage materials, catalyst carriers and biomedical materials. There are many methods for preparing phenolic resin microspheres, and commonly used synthesis methods include emulsion polymerization, suspension polymerization, template method, self-assembly, etc.

[0004] The related patent CN 112499625A discloses a special medicinal suspension phenolic resin microsphere and its preparation process of activated carbon sphere, discloses a special medicinal suspension phenolic resin microsphere preparation process, the main raw materials are phenol, formaldehyde, curing agent, suspending agent and solvent, the above raw materials are added to the reactor in the corresponding proportion, stirred and heated to react; then washed, filtered, dried and sieved to obtain phenolic resin microsphere. The invention also discloses a process for preparing activated carbon spheres using the prepared phenolic resin microspheres, by placing the phenolic resin microspheres in a carbonization activation furnace, passing inert gas for protection, then heating and carbonizing, activating, and finally pouring out from the reaction vessel, cooling and sieving to obtain activated carbon spheres. The invention adopts powdered phenolic resin as the carbon source material, the synthesis process is simple, the cost is low, and the raw materials are sufficient and easy to obtain. However, the activated carbon prepared by this technology has low strength and serious powder removal phenomenon. Its adsorption performance needs to be further improved when applied to the field of western medicine.

[0005] The related patent CN 106029218A discloses an oral medical adsorbent with increased strength, points out an oral medical adsorbent, and relates to an oral medical adsorbent composed of porous activated carbon with increased strength. The invention uses spherical furan resin as a carbon source to prepare activated carbon, and as an oral medical adsorbent, it can adsorb indole substances in patients with chronic renal failure or renal insufficiency, reduce the frequency of renal dialysis, and reduce patient symptoms. The carbon source of this technology is furan resin, and the resin material has great advantages in its own strength and heat resistance. However, the activated carbon adsorbent prepared by this technology has a narrow adsorption width, and the adsorbent is not easy to be mass-produced. Because furan is a carcinogen, the difficulty of the process of preparing the medical adsorbent is relatively large, which limits the application field of the adsorbent.

[0006] The related patent CN 115650227A discloses a method of using polyvinyl acetal modified phenolic resin microspheres as carbonization raw materials, preparing activated carbon balls through a carbonization activation process, and then grinding the phenolic resin microspheres from the millimeter level to the 2-10 micron level by ball milling to meet the requirements of injection medicine. The invention can effectively solve the performance parameters of activated carbon for injection, and can meet the standards used in the industry through the detection of adsorption performance and metal, ash and impurities. However, the invention can only be applied to injection adsorbents, and other metals and non-metallic substances are easily mixed in during the grinding process, which increases the impurity removal process procedures at the back end and the number of operating procedures. Summary of the invention

[0007] In view of the shortcomings and deficiencies of the existing preparation of phenolic resin microspheres and the preparation of spherical activated carbon using phenolic resin microspheres as carbon sources, such as insufficient strength, easy powdering, complex processing such as back-end impurity removal and purification, and the difficulty in obtaining raw materials or the presence of carcinogenic raw materials, the present invention aims to provide a modified phenolic resin microsphere, which utilizes propanol to modify phenolic resin so that it has the characteristics of complex linear curing, high strength, high temperature resistance, high roundness rate, etc., and uses it as a carbon source to prepare carbon balls in a carbonization furnace, and then uses the carbon balls as raw materials to be activated at high temperature using water vapor in an activation furnace to prepare activated carbon balls. The prepared activated carbon balls can be used in medical adsorption materials, chemical protection clothing adsorption materials, blood purification applications, etc.

[0008] The present invention is achieved through the following technical solutions:

[0009] A modified phenolic resin microsphere is prepared by the following steps:

[0010] S1. Stir phenol and 9.8% sulfuric acid in a three-necked flask equipped with a stirrer, a thermometer and a condenser, raise the temperature to not less than 100°C and react for not less than 30 minutes, then add a 37% formalin solution dropwise, then connect a reflux condenser, continue heating, and keep the temperature boiling until the irritating odor disappears, to obtain a mixture A;

[0011] S2, adding an acid-base regulator to the mixture A until the pH reaches 3, and performing distillation to remove excess water to obtain a mixture B;

[0012] S3, after heating the mixture B, add propanol and toluene until no more water is produced, add an acid-base regulator until the pH is 7-8, and obtain modified phenolic resin microspheres.

[0013] Preferably, the mass ratio is phenol: sulfuric acid: formalin solution: propanol: toluene = 20:110:15:20:350.

[0014] Preferably, in S1, the heating rate of stirring and heating to not less than 100°C is 8°C-10°C / min;

[0015] The rate of adding the formalin solution with a mass concentration of 37% drop by drop is 3-4 drops / second;

[0016] After the reflux condenser is connected, the heating process is as follows: continue heating the temperature to 100°C at a rate of 8°C-10°C / min, and keep the temperature at 100°C for no less than 5 hours until the irritating smell disappears.

[0017] Preferably, in S2, the acid-base regulator is a sodium hydroxide solution with a mass concentration of 10%, and the ratio of the sodium hydroxide solution to phenol is 90 mL:20 g.

[0018] Preferably, in S3, the mixture C is heated to 80-100° C. for not less than 20 min;

[0019] The acid-base regulator is a sodium hydroxide solution with a mass concentration of 10%;

[0020] The modified phenolic resin microspheres have a particle size of 0.2-1.2 mm, a strength after constant weight of more than 30 N, a sphericity of more than 90%, and a moisture content of 30-55%.

[0021] A carbon ball is prepared from the modified phenolic resin microspheres, specifically comprising:

[0022] The modified phenolic resin microspheres are placed in a carbonization furnace, an inert gas is introduced at a flow rate of 10 to 20 mL / min for protection, the temperature is rapidly raised to not less than 200° C. at a rate of 5° C. / min, and the temperature is maintained for 60 to 90 minutes to complete the curing;

[0023] Under nitrogen protection, continue to heat at a rate of 5.0-7.0°C / min to no less than 850°C, maintain the temperature for 1-2 hours, complete carbonization, and produce carbon balls.

[0024] Preferably, the carbon ball has a particle size of 0.4-1.0 mm, a strength after constant weight of >35N, a sphericity of >95%, and a moisture content of <10%.

[0025] An activated carbon ball is prepared from the carbon ball, specifically comprising:

[0026] The carbon balls are placed in an activation furnace, inert gas is introduced for protection, the temperature is quickly raised to 850-900°C, the introduction of inert gas is stopped, and then deionized water vapor is introduced. This is continued for 2-5 hours while the temperature is kept constant at 180-220°C, the introduction of water vapor and heating are stopped, and nitrogen is introduced to cool down to room temperature to complete the activation of the carbon balls to make activated carbon balls.

[0027] Preferably, the activated carbon ball has a particle size of 0.4-0.8 mm, a strength after constant weight of >35N, a sphericity of >95%, a moisture content of <1.0%, and a specific surface area of ​​>1000m 2 / g, total pore volume>0.40cm 3 / g, average pore size>0.5n, pH is 7-8.

[0028] Preferably, the mass ratio of the introduced deionized water vapor to the modified phenolic resin microspheres is 20 to 50:1.

[0029] The above particle size test is carried out using a micron laser particle size analyzer.

[0030] The above sphericity is measured by a screw micrometer with an accuracy of 0.01mm. The measured sphericity is the average of the sphericity of each resin ball. The calculation method is shown in the following formula:

[0031]

[0032] Where: Di short diameter - the shortest diameter of the i-th resin ball, mm;

[0033] Di long diameter - the longest diameter of the ith resin ball, mm.

[0034] The above water content is measured by a rapid moisture meter.

[0035] The above strength is measured using a compressive strength tester.

[0036] The carbonization furnace is made of quartz or 310s stainless steel.

[0037] The above-mentioned inert gas is nitrogen (N2>99.998%, mass concentration).

[0038] The above specific surface area, pore volume and pore diameter were tested using 77.3k and N2.

[0039] When the pH value of the activated carbon balls obtained above is 8-9, a hydrochloric acid solution with a mass concentration of 10% is added to adjust the pH during the acidification treatment to obtain activated carbon balls with a pH value of 7-8.

[0040] Compared with the prior art, the present invention has at least the following technical effects:

[0041] The invention provides a modified phenolic resin microsphere, which utilizes propanol to modify the phenolic resin so that it has the characteristics of complex linear curing, high strength, high temperature resistance, high roundness rate, etc., and uses the propanol as a carbon source to prepare carbon balls through a carbonization furnace, and then uses the carbon balls as raw materials to perform high-temperature activation using water vapor through an activation furnace to prepare activated carbon balls. The prepared activated carbon balls can be used in pharmaceutical adsorption materials, chemical protection clothing adsorption materials, blood purification application fields, etc.

[0042] The modified phenolic resin microspheres and the carbon balls and activated carbon balls prepared therefrom have the following advantages:

[0043] (1) Propanol modified phenolic resin, the raw materials are synthetic chemical materials, which are abundant in source, low in price and do not contain carcinogens. The synthesis process is simple and easy to operate, which is convenient for large-scale production;

[0044] (2) The prepared modified phenolic resin has high strength, high ball rate and high temperature resistance. After carbonization activation, the ball rate is still above 90% and the strength is maintained above 40N;

[0045] (3) The carbon powder contains little impurities, and the porosity, pore volume, pore diameter and specific surface area after activation can meet the requirements of medical adsorbents, blood perfusion, and energy and gas storage;

[0046] (4) Safety and environmental protection. The present invention mainly uses synthetic materials as carbon sources with low impurity content. The waste gas, waste liquid and waste impurities generated during the carbonization process are relatively small and can be recycled after adsorption treatment, so there is no environmental problem. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a scanning electron microscope image of the modified phenolic resin microspheres prepared in Example 1, with a scale of 100 μm.

[0048] Figure 2 This is a schematic diagram of the carbon balls prepared in Example 1;

[0049] Figure 3 This is a schematic diagram of the activated carbon balls prepared in Example 1;

[0050] Figure 4 It is a schematic diagram of the adsorption and desorption isotherm curves of the detection;

[0051] Figure 5A schematic diagram of the pore volume and pore area distribution calculated based on the adsorption isotherm in the test;

[0052] Figure 6 This is a schematic diagram of the pore volume and pore area distribution calculated based on the desorption isotherm (Desorption Isotherm).

[0053] Figure 7 Schematic diagram of the specific surface area of ​​the second BET multi-point method;

[0054] Figure 8 Schematic diagram of detecting specific surface area using the three Langmuir multi-point methods.

[0055] In the figure, A-Adsorption Isotherm; D-Desorption Isotherm; DETAILED DESCRIPTION

[0056] The embodiments of the present invention will be described in detail below in conjunction with examples. However, those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be construed as limiting the scope of the present invention. The specific conditions not specified in the examples are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used without indicating the manufacturer are all conventional products that can be purchased commercially.

[0057] All the percentages of raw materials below are expressed as mass concentrations.

[0058] Embodiment 1:

[0059] 1. Preparation of modified phenolic resin microspheres (carbon source):

[0060] Take 20g of phenol and 110g of 9.8% sulfuric acid, stir in a three-necked flask equipped with a stirrer, thermometer and condenser, heat to 100℃ and react for 30min, add 15g of 37% formalin dropwise, then connect the reflux condenser, continue heating at 100℃ and boiling for 5h, until the irritating odor disappears.

[0061] 90 mL of 10% NaOH solution was added to the solution to neutralize it until the pH value reached 3, and the excess water was continued to be distilled off.

[0062] The mixture was heated at 80°C. After 20 minutes of reaction, 20 g of propanol and 350 g of toluene were added to the mixture. The reaction was stopped when water was no longer produced.

[0063] The obtained resin was neutralized with 10% NaOH solution until the pH value was 7-9 to obtain modified phenolic resin microspheres.

[0064] The particle size of the modified phenolic resin microspheres is 0.2-1.0 mm, the strength is 31N (after constant weight), the sphericity is >95%, and the moisture content is 55%.

[0065] 2. Preparation of carbon balls

[0066] Place the modified phenolic resin microspheres in a carbonization furnace, introduce nitrogen gas for protection, and quickly heat up to 150°C to complete curing;

[0067] Under nitrogen protection, the temperature was continued to be raised to 850°C at a rate of 5.0°C / min and maintained at that temperature for 2h to complete carbonization and produce carbon balls.

[0068] The particle size of the carbon ball is 0.4-1.0mm, the strength is 34N (after constant weight), the sphericity is >95%, and the moisture content is <10%.

[0069] 3. Preparation of activated carbon balls

[0070] The carbon balls were placed in an activation furnace, and nitrogen gas was introduced for protection. The temperature was quickly raised to 850°C, and the introduction of nitrogen gas was stopped. Water vapor was introduced instead. The temperature was maintained constant for 2 hours to complete the activation of the carbon balls and make activated carbon balls.

[0071] The particle size of activated carbon balls is 0.4-0.8mm, the strength is 38N (after constant weight), the spherical rate is 95%, the moisture content is 1.6%, and the specific surface area is 1100m 2 / g, total pore volume 0.45cm 3 / g, average pore size 1.25nm.

[0072] like Figure 1 The figure shows a scanning electron microscope image of the modified phenolic resin microspheres prepared in Example 1, with a scale of 100 μm. The electron microscope image is a 40-fold magnification image, and the particle size is 0.1 mm.

[0073] like Figure 2 , which is a schematic diagram of the carbon balls prepared in Example 1;

[0074] like Figure 3 Shown is a schematic diagram of the activated carbon balls prepared in Example 1.

[0075] Embodiment 2:

[0076] (1) Preparation of modified phenolic resin microspheres (carbon source):

[0077] Take 20g of phenol and 110g of 9.8% sulfuric acid and stir them in a three-necked flask equipped with a stirrer, a thermometer and a condenser. Heat the mixture to 100℃ and react for 40min, add 15g of 37% formalin dropwise, then connect a reflux condenser and continue heating at 100℃ and boiling for 6h until the irritating odor disappears.

[0078] 90 mL of 10% NaOH solution was added to the solution to neutralize it until the pH value reached 3, and the excess water was continued to be distilled off.

[0079] The mixture was heated at 100°C. After 30 minutes of reaction, 20 g of propanol and 350 g of toluene were added to the mixture. The reaction was stopped when water was no longer produced.

[0080] The obtained resin was neutralized with 10% NaOH solution until the pH value was 7-9.

[0081] The particle size of the modified phenolic resin microspheres is 0.2-1.0 mm, the strength is 35N (after constant weight), the sphericity is 95%, and the moisture content is 45%.

[0082] 2. Preparation of carbon balls

[0083] The modified phenolic resin microspheres were placed in a carbonization furnace, nitrogen gas was introduced for protection, and the temperature was quickly raised to 180°C to complete the curing; under nitrogen protection, the temperature was continued to be raised to 850°C at a rate of 5.5°C / min, and the temperature was maintained for 2 hours to complete the carbonization and make carbon balls.

[0084] The particle size of the carbon ball is 0.4-1.0mm, the strength is 36N (after constant weight), the sphericity is 95%, and the moisture content is 6%.

[0085] 3. Preparation of activated carbon balls

[0086] The carbon balls were placed in an activation furnace, and nitrogen gas was introduced for protection. The temperature was quickly raised to 850°C, and the introduction of nitrogen gas was stopped. Water vapor was introduced instead at a rate of 500 L / h. The temperature was maintained constant for 4 hours to complete the activation of the carbon balls and make activated carbon balls.

[0087] The particle size of activated carbon balls is 0.4-0.8mm, the strength is 40N (after constant weight), the spherical rate is 97%, the moisture content is 0.98%, and the specific surface area is 1450m 2 / g, total pore volume 0.57cm 3 / g, average pore size 1.98nm.

[0088] Embodiment 3:

[0089] (1) Preparation of modified phenolic resin microspheres (carbon source):

[0090] Take 20g of phenol and 110g of 9.8% sulfuric acid and stir them in a three-necked flask equipped with a stirrer, a thermometer and a condenser. Heat the mixture to 100℃ and react for 40min, add 15g of 37% formalin dropwise, then connect a reflux condenser and continue heating at 100℃ and boiling for 6h until the irritating odor disappears.

[0091] 90 mL of 10% NaOH solution was added to the solution to neutralize it until the pH value reached 3, and the excess water was continued to be distilled off.

[0092] The mixture was heated at 100°C. After 50 minutes of reaction, 20 g of propanol and 350 g of toluene were added to the mixture. The reaction was stopped when water was no longer produced.

[0093] The obtained resin was neutralized with 10% NaOH solution until the pH value was 7-9.

[0094] The particle size of the modified phenolic resin microspheres is 0.2-1.0 mm, the strength is 35N (after constant weight), the sphericity is 98%, and the water content is 40%.

[0095] 2. Preparation of carbon balls

[0096] The modified phenolic resin microspheres were placed in a carbonization furnace, nitrogen gas was introduced for protection, and the temperature was quickly raised to 200°C to complete the curing; under nitrogen protection, the temperature was continued to be raised to 850°C at a rate of 5.5°C / min, and the temperature was maintained for 3 hours to complete the carbonization and make carbon balls.

[0097] The particle size of the carbon ball is 0.4-1.0mm, the strength is 38N (after constant weight), the sphericity is 95%, and the moisture content is 5%.

[0098] 3. Preparation of activated carbon balls

[0099] The carbon balls were placed in an activation furnace, and nitrogen gas was introduced for protection. The temperature was quickly raised to 850°C, and the introduction of nitrogen gas was stopped. Water vapor was introduced instead at a rate of 600 L / h. The temperature was maintained constant for 5 hours to complete the activation of the carbon balls and make activated carbon balls.

[0100] The particle size of activated carbon balls is 0.4-0.8mm, the strength is 42N (after constant weight), the spherical rate is 92%, the moisture content is 0.5%, and the specific surface area is 1661m 2 / g, total pore volume 0.81cm 3 / g, average pore size 2.64nm.

[0101] Embodiment 4:

[0102] (1) Preparation of modified phenolic resin microspheres (carbon source):

[0103] Take 20g of phenol and 110g of 9.8% sulfuric acid and stir them in a three-necked flask equipped with a stirrer, a thermometer and a condenser. Heat the mixture to 100℃ and react for 40min, add 15g of 37% formalin dropwise, then connect a reflux condenser and continue heating at 100℃ and boiling for 5h until the irritating odor disappears.

[0104] 90 mL of 10% NaOH solution was added to the solution to neutralize it until the pH value reached 3, and the excess water was continued to be distilled off.

[0105] The mixture was heated at 100° C. and reacted for 40 minutes. Then, 20 g of propanol and 350 g of toluene were added to the mixture. The reaction was stopped when water was no longer produced.

[0106] The obtained resin was neutralized with 10% NaOH solution until the pH value was 7-9.

[0107] The particle size of the modified phenolic resin microspheres is 0.2-1.0 mm, the strength is 35N (after constant weight), the sphericity is 93%, and the water content is 50%.

[0108] 2. Preparation of carbon balls

[0109] The modified phenolic resin microspheres were placed in a carbonization furnace, nitrogen gas was introduced for protection, and the temperature was quickly raised to 220°C to complete the curing; under nitrogen protection, the temperature was continued to be raised to 850°C at 6.0°C / min, and the temperature was maintained for 2 hours to complete the carbonization and make carbon balls.

[0110] The particle size of the carbon ball is 0.4-1.12mm, the strength is 35N (after constant weight), the sphericity is 95%, and the moisture content is 3%.

[0111] 3. Preparation of activated carbon balls

[0112] The carbon balls were placed in an activation furnace, and nitrogen gas was introduced for protection. The temperature was quickly raised to 850°C, and the introduction of nitrogen gas was stopped. Water vapor was introduced instead at a rate of 700 L / h. The temperature was maintained constant for 6 hours to complete the activation of the carbon balls and make activated carbon balls.

[0113] The particle size of activated carbon balls is 0.4-0.8mm, the strength is 45N (after constant weight), the spherical rate is 96%, the moisture content is 0.3%, and the specific surface area is 1680m 2 / g, total pore volume 1.02cm 3 / g, average pore size 2.933nm.

[0114] The activated carbon balls prepared in the above embodiments are alkaline through pH test, and the pH value is generally between 9 and 10. Therefore, it is necessary to acidify them to ensure that the pH value of the finished activated carbon balls is generally between 7 and 8.

[0115] Experimental verification:

[0116] The product prepared in Example 1 above was selected as a sample for testing.

[0117] Test principle: static capacity method.

[0118] Test 1: Porous materials - pore distribution analysis

[0119] like Figure 4 As shown, it is a schematic diagram of adsorption and desorption isotherm curves, where A-Adsorption Isotherm; D-Desorption Isotherm.

[0120] like Figure 5 , which is a schematic diagram of pore volume and pore area distribution calculated based on adsorption isotherm;

[0121] like Figure 6 , which is a schematic diagram of pore volume and pore area distribution calculated based on the desorption isotherm.

[0122] According to the adsorption isotherm calculation results, Figure 5 And as shown in Table 1.

[0123] Table 1

[0124]

[0125] According to the desorption isotherm calculation results, Figure 6 And as shown in Table 2.

[0126] Table 2

[0127]

[0128] Test 2: BET multi-point method specific surface area test Test principle: BET multi-point method as Figure 7 As shown in the figure, it is a schematic diagram of the specific surface area of ​​the BET multi-point method; the test results of the BET multi-point method are as follows Figure 7 As shown in Tables 3 and 4.

[0129] Table 3 BET multi-point test results

[0130]

[0131] Table 4 BET multi-point method data table

[0132]

[0133] BET formula:

[0134]

[0135] Where: (P / P0) / [V(1-P / P0)]: ordinate of the BET equation; P0: saturated vapor pressure of the adsorbate at the adsorption temperature; Vm: monolayer saturated adsorption capacity of the adsorbent to the adsorbate, cm 3 / g; C: constant related to the adsorption performance of the adsorbent; S: specific surface area; am: cross-sectional area of ​​the adsorbate molecule, m 2 ; 22414: Volume occupied by 1 mol of gas under standard conditions, cm 3 ; P / P0: relative pressure; P: pressure after adsorption equilibrium, bar; V: adsorption amount of adsorbent on adsorbate at adsorption equilibrium pressure P, cm 3 / g; a: slope of the fitted line; b: intercept of the fitted line; NA: Avogadro constant, 6.02*10^23.

[0136] Test 3: Langmuir surface area

[0137] Test principle: Langmuir multi-point method

[0138] like Figure 8 The figure shows the schematic diagram of the specific surface area using the Langmuir multi-point method.

[0139] The results of the Langmuir multi-point method are as follows Figure 8 As shown in Tables 5 and 6.

[0140] Table 5 Langmuir multi-point test results:

[0141]

[0142] Table 6 Langmuir multi-point method data table

[0143]

[0144]

[0145] Langmuir equation:

[0146]

[0147] Where: P / V: ordinate of Langmuir equation; Vm: monolayer saturated adsorption capacity of adsorbent to adsorbate, cm 3 / g; C: constant related to the adsorption performance of the adsorbent; S: specific surface area; am: cross-sectional area of ​​the adsorbate molecule, m 2 ; 22414: Volume occupied by 1 mol of gas under standard conditions, cm 3; P: pressure after adsorption equilibrium, bar; V: adsorption amount of adsorbent on adsorbate at adsorption equilibrium pressure P, cm 3 / g; a: slope of the fitted line; b: intercept of the fitted line; NA: Avogadro constant, 6.02×10 23 .

[0148] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A modified phenolic resin microsphere, characterized in that: It is prepared by the following steps: S1. Stir phenol and 9.8% sulfuric acid in a three-necked flask equipped with a stirrer, a thermometer and a condenser, raise the temperature to not less than 100°C and react for not less than 30 minutes, then add a 37% formalin solution dropwise, then connect a reflux condenser, continue heating, and keep the temperature boiling until the irritating odor disappears, to obtain a mixture A; The heating rate of the stirring heating to not less than 100°C is 8°C-10°C / min; The rate of dropwise addition of the 37% formalin solution is 3-4 drops / second; After the reflux condenser is connected, the heating process is as follows: continue heating the temperature to 100°C at a rate of 8°C-10°C / min, and keep the temperature at 100°C for no less than 5 hours until the irritating smell disappears; S2, adding an acid-base regulator to the mixture A until the pH reaches 3, and performing distillation to remove excess water to obtain a mixture B; S3, after heating the mixture B, adding propanol and toluene until water is no longer generated, adding an acid-base regulator until the pH is 7-8, to obtain modified phenolic resin microspheres; The mass ratio is phenol: sulfuric acid with a mass concentration of 9.8%: formalin solution: propanol: toluene = 20:110:15:20:350; The modified phenolic resin microspheres have a particle size of 0.2-1.2 mm, a strength after constant weight of >30 N, a sphericity of >90%, and a moisture content of 30-55%; The mixture B is heated to 80-100° C. for not less than 20 min; The acid-base regulator is a sodium hydroxide solution with a mass concentration of 10%.

2. The modified phenolic resin microsphere according to claim 1, characterized in that: In S2, the acid-base regulator is a sodium hydroxide solution with a mass concentration of 10%, and the ratio of the sodium hydroxide solution to phenol is 90 mL:20 g.

3. A carbon ball, characterized in that: The modified phenolic resin microspheres are prepared according to any one of claims 1 to 2, and specifically include: The modified phenolic resin microspheres as claimed in claim 1 are placed in a carbonization furnace, an inert gas is introduced at a flow rate of 10-20 mL / min for protection, the temperature is rapidly raised to not less than 200° C. at a rate of 5° C. / min, and the temperature is kept for 60-90 minutes to complete the curing; Under nitrogen protection, continue to heat at 5.0-7.0°C / min to no less than 850°C, maintain the temperature for 1-2 hours, complete carbonization, and make carbon balls; The carbon ball has a particle size of 0.4-1.0 mm, a strength after constant weight of more than 35 N, a sphericity of more than 95%, and a moisture content of less than 10%.

4. An activated carbon ball, characterized in that: The carbon ball is prepared from the carbon ball as claimed in claim 3, and specifically comprises: The carbon balls as claimed in claim 3 are placed in an activation furnace, inert gas is introduced for protection, the temperature is rapidly raised to 850-900° C., the introduction of inert gas is stopped, and then deionized water vapor is introduced, and the temperature is maintained at 180-220° C. for 2-5 hours, the introduction of water vapor and heating are stopped, and nitrogen is introduced to cool down to room temperature to complete the activation of the carbon balls to prepare activated carbon balls; The activated carbon ball has a particle size of 0.4-0.8 mm, a strength after constant weight of >35N, a sphericity of >95%, a moisture content of <1.0%, and a specific surface area of ​​>1000m 2 / g, total pore volume>0.40cm 3 / g, average pore size>0.5nm, pH 7-8; The mass ratio of the introduced deionized water vapor to the modified phenolic resin microspheres is 20-50:1.

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