Mixing device and high specific surface area material mixing method

Abstract

The present invention provides a mixing device and a method for mixing high-specific surface area materials. The mixing device comprises a mixing unit and a grinding unit, wherein the material outlet of the mixing unit is connected to the material inlet of the grinding unit. The mixing unit comprises a mixing barrel, a scraper, a reamer, a spray device, and a shielding plate for barrel wall holes. The grinding unit comprises a grinding barrel, a grinding disc, a grinding disc fixing device, and a material receiving bin. The mixing device provided by the present invention significantly improves the mixing efficiency of high-specific surface area materials with other substances, while substantially maintaining the specific surface area of ​​the high-specific surface area material before and after mixing, thereby ensuring its performance.

Description

Technical Field

[0001] The invention belongs to the field of materials, and relates to a mixing device and a material mixing method, in particular to a mixing device and a high specific surface area material mixing method. Background Art

[0002] To maintain the high surface area properties of novel carbon materials before and after mixing and ensure uniform mixing, the main methods currently used to mix novel carbon materials with high surface areas, such as graphene and carbon nanotubes, with reactive ligands are stirring, ultrasonication, ball milling, and centrifugal mixing. Stirring and ultrasonication systems have low concentrations, typically ranging from 0.1 to 10 mg / ml. This results in long mixing and drying times, and the total amount of mixed material is low, making them unsuitable for industrial production. Ball milling, without the addition of a lubricant, can easily disrupt the morphology of novel carbon materials with long chains and large surface areas. Adding a lubricant requires subsequent, tedious steps such as impurity removal. Centrifugal mixing is only suitable for systems where neither material is soluble in water, and the mixing amount can range from 1 mg to 10 g, which is insufficient for kilogram-scale production. High-speed mixing is a highly efficient method for mixing materials, but requires a reamer designed to minimize the impact of shear forces on the morphology of the novel carbon materials and to ensure uniform mixing.

[0003] Modified new carbon materials often have excellent catalytic and conductive properties. However, the preparation of modified new carbon materials often requires mixing and then calcination. The mixing process is cumbersome and time-consuming, and the amount of material processed each time is small. This is the key reason why modified new carbon materials cannot be produced at the kilogram level, which greatly hinders the industrial application of materials. Traditional high-speed mixing has high shear force, which will destroy the morphology of the new carbon material during mixing and reduce the specific surface area of ​​the material. At the same time, after high-speed mixing, the material needs to be discharged, dried, and ground, which is inefficient.

[0004] CN107261930A discloses a powder pulverizing, feeding, and mixing device, comprising a pulverizing mechanism and a feeding and mixing mechanism arranged in sequence above and below. The pulverizing mechanism comprises a pulverizing drum, a pulverizing reamer, a pulverizing motor, and a discharge pipe. The upper and lower portions of the pulverizing drum are respectively provided with a powder inlet and a powder outlet. The pulverizing reamer is pivotally connected to the pulverizing drum, the output end of the pulverizing motor is transmission-connected to the pulverizing reamer, and the discharge pipe is connected to the powder outlet of the pulverizing drum. The feeding and mixing mechanism comprises a mixing tank, a powder feeding plate, a powder weighing sensor, and a powder pushing plate. The upper end of the mixing tank is provided with a feeding opening, the powder feeding plate is arranged below the discharge pipe, the powder feeding plate is fixed to the powder weighing sensor and located above the feeding opening, and the powder pushing plate is slidably arranged on the powder feeding plate. However, this prior art solution can only be used for mixing general powder materials and is not suitable for mixing high-specific-surface-area powder materials. Summary of the Invention

[0005] In view of the above problems existing in the prior art, the purpose of the present invention is to provide a mixing device and a method for mixing high specific surface area materials. The mixing device provided by the present invention can mix high specific surface area materials and ligands at high speed and produce powder, realizing the integration of mixing, drying and grinding, and greatly improving the mixing efficiency of high specific surface area materials and other substances. In the present invention, the high specific surface area material refers to a material with a specific surface area of ​​100m 2 / g or more materials.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a mixing device, comprising a mixing unit and a grinding unit, wherein a material outlet of the mixing unit is connected to a material inlet of the grinding unit;

[0008] The mixing unit includes a mixing barrel, a scraper, a reamer, a spray device, and a barrel wall hole shielding plate. The inner wall of the side of the mixing barrel is provided with a hole. The number of the reamers is three or more, for example, three, four, or five, and at least two of the reamers rotate in opposite directions. The scraper and the reamers are arranged in sequence from top to bottom in the mixing barrel. The spray device is located above the mixing barrel. The barrel wall hole shielding plate is located on the inner wall of the side of the mixing barrel.

[0009] The grinding unit includes a grinding machine barrel, a grinding disc, a grinding disc fixing device and a material receiving bin. The grinding disc fixing device is located above the grinding disc and is used to fix the grinding disc. The grinding disc and the grinding disc fixing device are both located in the grinding machine barrel. The material outlet of the grinding machine barrel is communicated with the material receiving bin. The grinding disc fixing device is provided with a heating device.

[0010] In the mixing device provided by the present invention, the design of the multiple reamers of the mixing unit can achieve material convection through different reamer rotation directions, thereby achieving sufficient mixing of the materials. The non-identical rotation directions of the reamers mean that some reamers rotate clockwise and some rotate counterclockwise, and not all reamers rotate in the same direction, thereby ensuring sufficient mixing of the materials.

[0011] In the present invention, the scraper can scrape the material off the wall of the mixing barrel to ensure that all materials are involved in the mixing. The number of scrapers can be set as needed, for example, two scrapers can be set.

[0012] In the mixing device provided by the present invention, the spraying device can realize uniform spraying of the infiltration medium. The spraying device can be an automatic spraying device.

[0013] The present invention provides holes on the side inner wall of the mixing barrel, and also provides a barrel wall hole shielding plate, so that the barrel wall hole shielding plate can be used to cover the holes on the side inner wall of the mixing barrel when stirring and mixing is required, and the barrel wall hole shielding plate can be pulled up to expose the holes on the side inner wall of the mixing barrel when granulation is required. This can be done by scraping the material particles out of the holes on the mixing barrel wall with a scraper after the material is convectively mixed to achieve direct granulation, which is convenient for the next step of grinding and drying, so that the granulated product enters the heatable grinding disk of the grinding unit, realizing the integration of mixing, drying and grinding, and greatly improving the mixing efficiency of high specific surface area materials and other substances.

[0014] That is, the barrel wall hole shielding plate is used to shield or expose the holes on the inner wall of the side of the mixing barrel.

[0015] The heating device on the grinding disc fixing device can quickly dry the material during grinding, so that the material can be quickly powdered. The heating device can be a heating wire.

[0016] In the present invention, the inlet of the grinding barrel is the material inlet of the grinding unit.

[0017] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the technical objectives and beneficial effects of the present invention can be better achieved and realized.

[0018] As a preferred technical solution of the present invention, the reamer is a rectangular column reamer without sharp corners. This reamer can significantly reduce the shear force of the reamer and can be used to replace the commonly used blade reamer. It can basically maintain the specific surface area of ​​the high specific surface area material before and after mixing, ensuring its performance.

[0019] Preferably, the scraper and the reamer both rotate about a straight line perpendicular to the bottom surface of the mixing barrel.

[0020] Preferably, the length of the reamer is consistent with the inner radius of the mixing barrel. Such a design can ensure that the bottom materials can be turned over and stirred.

[0021] Preferably, there are three reamers, and the reamers are respectively the first reamer, the second reamer and the third reamer from top to bottom according to their positions in the mixing barrel.

[0022] The first reamer, the second reamer and the third reamer are respectively arranged on different nested axes of the coaxial nested rotation axes. This design enables the rotation direction of each reamer to be independent and not dependent on the rotation direction of other reamers.

[0023] Preferably, the first and third reamers rotate in the same direction, while the second reamer rotates in the opposite direction. This allows for better convection and minimizes the cost of the device by requiring too many reamers. For example, the first and third reamers rotate clockwise, while the second reamer rotates counterclockwise.

[0024] Preferably, the reamer is a metal blade.

[0025] Preferably, the scraper is a polytetrafluoroethylene blade.

[0026] As a preferred technical solution of the present invention, the mixing barrel has a double-layered wall structure, with holes provided in the inner side wall. The bottom of the mixing barrel is provided with a discharge port, which communicates with the gap between the inner and outer walls of the double-layered structure. In the present invention, the discharge port of the mixing barrel serves as the material outlet of the mixing unit.

[0027] This design of the mixing barrel enables the material to enter the gap between the inner and outer barrel walls through the holes on the inner side barrel wall during granulation, and then be discharged from the discharge port at the bottom of the mixing barrel.

[0028] As a preferred technical solution of the present invention, the grinding disc is made of zirconium oxide-plated 310 stainless steel. This material can avoid the introduction of other metal impurities.

[0029] Preferably, the grinding disc has a concave conical pore. Centrifugal force forces the material from the center to the narrow edge, grinding it from large particles to nanometer-scale powder. A heating wire can also be installed inside the grinding disc for heating and drying.

[0030] Preferably, the grinding disc fixing device is made of stainless steel.

[0031] Preferably, the grinding barrel is located in a receiving silo.

[0032] Preferably, a gap is provided at the bottom of the grinding barrel, and the ground material enters the receiving bin through the gap at the bottom of the grinding barrel.

[0033] As a preferred technical solution of the present invention, the material receiving bin is connected to a particle size tester. A stream of air can be introduced to carry the powder into the particle size tester, thereby enabling real-time monitoring of the powder particle size.

[0034] Preferably, the mixing barrel is arranged on a telescopic rod.

[0035] Preferably, the mixing device further comprises a control panel.

[0036] In a second aspect, the present invention provides a method for mixing high specific surface area materials, wherein the mixing method uses the mixing device as described in the first aspect, comprising the following steps:

[0037] The holes on the side inner wall of the mixing barrel are covered with a barrel hole shield, and the high specific surface area material and the ligand are added to the mixing barrel. The reamer is rotated at a first speed to pre-mix the powder; the pre-mixed powder is sprayed on the pre-mixed powder, and the reamer is rotated at a second speed, and the scraper is rotated to mix the materials; after mixing, the barrel hole shield is moved to expose the holes on the side inner wall of the mixing barrel, and granulation is carried out; the granulated product enters the grinding barrel and is ground on a preheated grinding disc. The ground product enters the material receiving bin to obtain the mixed powder;

[0038] Wherein, the second speed is greater than the first speed.

[0039] The high-surface-area material mixing method provided by the present invention can maintain the material's high specific surface area and other physicochemical properties while significantly reducing the time required for the mixing process, greatly improving the efficiency of material prefabrication, and further promoting the industrial production of modified novel carbon materials. This method is particularly suitable for high-surface-area materials such as graphene and carbon nanotubes.

[0040] The mixed powder obtained by the high specific surface area material mixing method provided by the present invention can be fed into the next step of sintering after being loaded.

[0041] In the present invention, the purpose of first using a low-speed rotary reamer and then a high-speed rotary reamer is to reduce the shear force on the material during mixing by the low-speed cylindrical rotary reamer, thereby maintaining a high specific surface area of ​​the material. The use of a polytetrafluoroethylene knife after mixing is for granulation, extruding the mixed carbon material into carbon spheres in the pores.

[0042] As a preferred technical solution of the present invention, the high specific surface area material includes nanocarbon material.

[0043] Preferably, the nano-carbon material includes graphene and / or carbon nanotubes.

[0044] Preferably, the first rotational speed is 20-50 r / min, such as 20 r / min, 30 r / min, 40 r / min or 50 r / min.

[0045] As a preferred technical solution of the present invention, the spraying medium includes any one of ethanol, ethylene glycol or water, or a combination of at least two of them.

[0046] Preferably, the second rotational speed is 300-1000 r / min, such as 300 r / min, 400 r / min, 500 r / min, 600 r / min, 700 r / min, 800 r / min, 900 r / min or 1000 r / min.

[0047] Preferably, the rotating speed of the scraper is 1-30 r / min, such as 1 r / min, 10 r / min, 20 r / min or 30 r / min.

[0048] Preferably, the material mixing time is 5-180 min, for example, 5 min, 10 min, 25 min, 50 min, 75 min, 100 min, 120 min, 140 min, 160 min or 180 min.

[0049] As a preferred technical solution of the present invention, the preheating temperature is above the boiling point of the spraying medium.

[0050] Preferably, the mixing method further comprises using a protective gas beam to blow the ground product in the receiving bin into a particle size tester for online particle size testing.

[0051] As a further preferred technical solution of the mixing method of the present invention, the method comprises the following steps:

[0052] Use the barrel wall hole shielding plate to cover the holes on the side inner wall of the mixing barrel, add the high specific surface area material and the ligand into the mixing barrel, rotate the reamer at a speed of 20-50r / min to premix the powder; spray on the premixed powder, rotate the reamer at a speed of 300-1000r / min, and rotate the scraper at a speed of 1-30r / min to mix the materials for 5-180min; after mixing, move the barrel wall hole shielding plate to expose the holes on the side inner wall of the mixing barrel for granulation; the granulated product enters the grinding machine barrel and is ground on the preheated grinding disc. The ground product enters the receiving bin to obtain the mixed powder. At the same time, a protective gas beam is used to blow the ground product in the receiving bin into the particle size tester for online particle size testing.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] (1) The mixing device provided by the present invention can mix high specific surface area materials and ligands at high speed and produce powder, realizing the integration of mixing, drying and grinding. It can be applied to the mixing of various new carbon materials and different ligands, greatly improving the mixing efficiency of high specific surface area materials and other substances. At the same time, it can basically maintain the specific surface area of ​​the high specific surface area material before and after the material mixing, thereby ensuring its performance.

[0055] (2) The high-specific-surface-area material mixing method provided by the present invention can maintain the material's high specific surface area and other physicochemical properties while significantly reducing the time required for the mixing process, greatly improving the efficiency of material prefabrication, and further promoting the industrial production of modified novel carbon materials. This method is particularly suitable for high-specific-surface-area materials such as graphene and carbon nanotubes. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 A schematic structural diagram of the mixing device provided in Example 1;

[0057] Figure 2 A schematic structural diagram of a reamer in the mixing device provided in Example 1;

[0058] Among them, 1-first reamer, 2-second reamer, 3-third reamer, 4-scraper, 5-spraying device, 6-barrel wall hole shielding plate, 7-grinding disc fixing device, 8-grinding disc, 9-mixing barrel, 10-grinding barrel, 11-material receiving bin, 12-telescopic rod, 13-particle size tester, 14-control panel;

[0059] Figure 3 This is a scanning electron microscope image of graphene oxide mixed according to the mixing method provided in Example 1. DETAILED DESCRIPTION

[0060] To better illustrate the present invention and facilitate understanding of the technical solution of the present invention, the present invention is further described in detail below. However, the following embodiments are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

[0061] The following are typical but non-limiting examples of the present invention:

[0062] Example 1

[0063] This embodiment provides a mixing device, the device is as follows Figure 1 As shown, it includes a mixing unit and a grinding unit, and the material outlet of the mixing unit is connected to the material inlet of the grinding unit;

[0064] The mixing unit includes a mixing barrel 9, a scraper 4, a reamer, a spray device 5 and a barrel wall hole baffle 6. The inner wall of the side of the mixing barrel 9 is provided with holes. The scraper 4 and the reamers are arranged in sequence from top to bottom in the mixing barrel 9. The spray device 5 is located above the mixing barrel 9; the barrel wall hole baffle 6 is located on the inner wall of the side of the mixing barrel 9.

[0065] The grinding unit includes a grinding barrel 10, a grinding disc 8, a grinding disc fixing device 7 and a material receiving bin 11. The grinding disc fixing device 7 is located above the grinding disc 8 and is used to fix the grinding disc 8. The grinding disc 8 and the grinding disc fixing device 7 are both located in the grinding barrel 10. The material outlet of the grinding barrel 10 is communicated with the material receiving bin 11. The grinding disc fixing device 7 is provided with a heating device (heating wire).

[0066] There are three reamers, which are the first reamer 1, the second reamer 2 and the third reamer 3 from top to bottom in the mixing barrel. The reamers are all rectangular column reamers without edges and corners. The length of the reamers is consistent with the inner radius of the mixing barrel 9. The first reamer 1 and the third reamer 3 have the same rotation direction, which is clockwise. The rotation direction of the second reamer is opposite to that of the first and second reamers, which is counterclockwise. The scraper 4 and the reamer rotate around a straight line perpendicular to the bottom surface (inner bottom surface) of the mixing barrel 9. The reamers are all metal blades, and the scraper 4 is a polytetrafluoroethylene blade. The first reamer 1, the second reamer 2 and the third reamer 3 are respectively arranged on different nested axes of the coaxial nested rotating axes, such as Figure 2 As shown, the rotation direction of each reamer is independent. Two scrapers 4 are provided.

[0067] The mixing barrel 9 has a double-layer structure, with holes provided on the inner side wall. A discharge port is provided at the bottom of the mixing barrel 9, communicating with the gap between the inner and outer barrel walls of the double-layer structure. With this design, when the barrel hole shielding plate 6 blocks the holes on the inner wall of the mixing barrel 9, mixing and stirring can be performed. After mixing and stirring, when granulation is to be performed, the barrel hole shielding plate 6 is pulled up to expose the holes on the inner wall of the mixing barrel 9. The scraper 4 can then be used to move the powder on the barrel wall through the holes on the inner wall of the mixing barrel 9 into the gap between the double-layer barrel walls of the mixing barrel 9, where it is then discharged through the discharge port of the mixing barrel 9 and into the grinding unit. The discharge port of the mixing barrel 9 is the material outlet of the mixing unit.

[0068] In the grinding unit, the grinding disc 8 is made of zirconium oxide-plated 310 stainless steel; the pores of the grinding disc 8 are concave cones. The grinding disc fixture 7 is made of stainless steel; the grinding barrel 10 is located in the material receiving bin 11, and the ground material enters the material receiving bin 11 through the gap at the bottom of the grinding barrel 10.

[0069] The material receiving bin 11 is connected to a particle size tester 13 , the mixing barrel 9 is arranged on a telescopic rod 12 , and the mixing device further includes a control panel 14 for controlling the entire mixing device.

[0070] This embodiment also provides a method for mixing high specific surface area materials using the above mixing device, the specific steps of which are as follows:

[0071] The holes on the side inner wall of the mixing barrel 9 are blocked by a barrel wall hole shield 6, and a high specific surface area material (1 kg of graphene oxide) and a ligand (0.5 kg of cobalt phthalocyanine) are added to the mixing barrel. The reamer is rotated at a speed of 50 r / min to premix the powder for 10 minutes. 100 g of a wetting medium (alcohol) is sprayed on the premixed powder. After 5 seconds, the reamer is rotated at a speed of 800 r / min, and the scraper 4 is rotated at a speed of 30 r / min to mix the materials for 20 minutes. After mixing, the barrel wall hole shield 6 is moved to expose the holes on the side inner wall of the mixing barrel 9, and granulation is carried out. The material is extruded to form a granulated product. The granulated product slides into the grinding machine barrel 10 and is ground on the grinding disc 8 that has been preheated to 85°C for 5 minutes. The ground product enters the receiving bin 11, completing the process of grinding the carbon particles into powder to obtain a mixed powder. At the same time, a nitrogen beam is used to blow the ground product in the receiving bin into the particle size tester 13 for online particle size testing.

[0072] The scanning electron microscope image of the mixed powder (graphene oxide) obtained by the preparation method provided in this embodiment is as follows: Figure 3 As shown in the figure, it can be seen that graphene oxide still maintains a layered structure and does not agglomerate due to material mixing.

[0073] Example 2

[0074] This embodiment provides a method for mixing high specific surface area materials using the mixing device described in Example 1, wherein the specific steps are as follows:

[0075] Use the barrel wall hole shielding plate 6 to block the holes on the side inner wall of the mixing barrel 9, add the high specific surface area material (1.5kg multi-walled carbon nanotubes) and the ligand (0.5kg porphyrin nickel) into the mixing barrel, rotate the reamer at a speed of 30r / min, and premix the powder for 10 minutes; spray 150g of the wetting medium (alcohol) on the premixed powder, and after 5s, rotate the reamer at a speed of 800r / min, and rotate the scraper 4 at a speed of 30r / min to mix the materials for 20 minutes; after mixing, move the barrel wall hole shielding plate 6 to expose the holes on the side inner wall of the mixing barrel 9, and granulate, and the material is extruded to form a granulated product; the granulated product slides into the grinding machine barrel 10, and is ground on the grinding disc 8 that has been preheated to 85°C for 5 minutes. The ground product enters the receiving bin 11, completing the process of grinding the carbon particles into powder to obtain a mixed powder.

[0076] Example 3

[0077] This embodiment provides a method for mixing high specific surface area materials using the mixing device described in Example 1, wherein the specific steps are as follows:

[0078] Use the barrel wall hole shielding plate 6 to block the holes on the side inner wall of the mixing barrel 9, add the high specific surface area material (1kg multi-walled carbon nanotubes) and the ligand (0.5kg porphyrin nickel) into the mixing barrel, rotate the reamer at a speed of 20r / min, and premix the powder for 20 minutes; spray 150g of the wetting medium (alcohol) on the premixed powder, and after 5s, rotate the reamer at a speed of 300r / min, and rotate the scraper 4 at a speed of 1r / min to mix the materials for 20 minutes; after mixing, move the barrel wall hole shielding plate 6 to expose the holes on the side inner wall of the mixing barrel 9, and granulate, and the material is extruded to form a granulated product; the granulated product slides into the grinding machine barrel 10, and is ground on the grinding disc 8 that has been preheated to 85°C for 5 minutes. The ground product enters the receiving bin 11, completing the process of grinding the carbon particles into powder to obtain a mixed powder.

[0079] Example 4

[0080] This embodiment provides a method for mixing high specific surface area materials using the mixing device described in Example 1, wherein the specific steps are as follows:

[0081] Use the barrel wall hole shielding plate 6 to block the holes on the side inner wall of the mixing barrel 9, add the high specific surface area material (3kg multi-walled carbon nanotubes) and the ligand (1kg porphyrin nickel) into the mixing barrel, rotate the reamer at a speed of 50r / min, and premix the powder for 10 minutes; spray 150g of the wetting medium (alcohol) on the premixed powder, and after 5s, rotate the reamer at a speed of 1000r / min, and rotate the scraper 4 at a speed of 25r / min to mix the materials for 20 minutes; after mixing, move the barrel wall hole shielding plate 6 to expose the holes on the side inner wall of the mixing barrel 9, and granulate, and the material is extruded to form a granulated product; the granulated product slides into the grinding machine barrel 10, and is ground on the grinding disc 8 that has been preheated to 85°C for 5 minutes. The ground product enters the receiving bin 11, completing the process of grinding the carbon particles into powder to obtain a mixed powder.

[0082] Comparative Example 1

[0083] The difference between the mixing device provided in this embodiment and the mixing device provided in Comparative Example 1 is that the third reamer 3 is not included, the position, shape and material of the first reamer 1 and the second reamer 2 are the same as those of the mixing device provided in Comparative Example 1, and the rotation direction is also the same as that of the mixing device in Example 1.

[0084] This comparative example also provides a method for mixing materials with a high specific surface area using the above-mentioned mixing device, which differs from the method in Example 1 only in that the mixing is performed using the mixing device provided in this example.

[0085] Comparative Example 2

[0086] The difference between the mixing device provided in this comparative example and the mixing device provided in Example 1 is that the first reamer 1, the second reamer 2 and the third reamer 3 all rotate clockwise, that is, the mixing unit in the mixing device provided in this comparative example cannot achieve material convection.

[0087] This comparative example also provides a method for mixing materials with a high specific surface area using the above-mentioned mixing device, which differs from the method in Example 1 only in that the mixing is performed using the mixing device provided in this comparative example.

[0088] Comparative Example 3

[0089] This comparative example adopts the following mixing method: the high specific surface area material (1.5kg multi-walled carbon nanotubes) and the ligand (0.5kg porphyrin nickel) are mixed, and then mixed with 1kg of ethanol, placed in an ultrasonic mixer and ultrasonicated at a frequency of 28Hz for 3h, followed by drying for 8h and grinding for 1min to obtain a mixed powder.

[0090] Comparative Example 4

[0091] This comparative example adopts the following mixing method: after mixing the high specific surface area material (1.5kg multi-walled carbon nanotubes) and the ligand (0.5kg porphyrin nickel), zirconium beads are added, ethanol is used as the ball milling solvent, and ball milling is carried out at a speed of 400r / min for 1h, followed by drying for 4h and grinding for 1min to obtain a mixed powder.

[0092] Test Method

[0093] The mixed powders provided in each embodiment and comparative example were calcined at 900° C. for 2 hours, and then tested using a specific surface area tester. The test results are shown in Table 1.

[0094] Table 1

[0095]

[0096]

[0097] Based on the above examples and comparative examples, it can be seen that the mixing methods provided in Examples 1-4 can maintain the material's high specific surface area and other physicochemical properties, while significantly reducing the time required for the mixing process, greatly improving the efficiency of material prefabrication, and better promoting the industrial production of modified new carbon materials. This method is particularly suitable for high specific surface area materials such as graphene and carbon nanotubes.

[0098] In Comparative Example 1, since the third reamer 3 is eliminated, the material at the bottom cannot be lifted up during the stirring process, and the material is deposited at the bottom of the mixing tube, forming agglomerates.

[0099] In Comparative Example 2, since the rotation directions of the reamer are not completely different, material convection cannot be achieved, resulting in the material rotating in one direction during the mixing process, easily agglomerating, and reducing the specific surface area of ​​the material.

[0100] Comparative Example 3 uses an ultrasonic mixing method, and the time it takes to process the same mass of material is significantly longer than that of Example 2, that is, the efficiency is lower than that of Example 2. In addition, due to the large ultrasonic mixing energy, when the material concentration is too high, the carbon material cannot be evenly dispersed. During the mixing process, agglomerates will form, which greatly reduces the specific surface area of ​​the material.

[0101] Comparative Example 4 uses a ball milling mixing method, and the time it takes to process the same mass of material is significantly longer than that of Example 2, that is, the efficiency is lower than that of Example 2. Moreover, the mixed product of this comparative example is not as good as that of Example 2 in terms of multi-point specific surface area, total adsorption pore volume, and most probable pore diameter, that is, this comparative example causes a large loss in the specific surface area of ​​the material after mixing. The zirconium bead ball milling of Comparative Example 4 achieves material mixing through collision and friction between zirconium beads, but the surface of high specific surface carbon materials has abundant functional groups, which will cause the material to lose unstable groups on the surface through friction, forming molecules with different charges, and forming adsorption. At the same time, during the collision process, the material will be subjected to excessive force, which will destroy the structure of the carbon material and greatly reduce the specific surface area of ​​the carbon material.

[0102] The applicant states that the present invention is intended to illustrate the detailed methods of the present invention through the above-described embodiments, but the present invention is not limited to the above-described detailed methods, that is, it does not mean that the present invention must rely on the above-described detailed methods in order to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions for various raw materials in the products of the present invention, addition of auxiliary ingredients, and selection of specific methods, etc., are all within the scope of protection and disclosure of the present invention.

Claims

1. A mixing device, characterized in that: The mixing device includes a mixing unit and a grinding unit, wherein the material outlet of the mixing unit is connected to the material inlet of the grinding unit; The mixing unit includes a mixing barrel, a scraper, a reamer, a spray device and a barrel wall hole shielding plate. The inner wall of the side of the mixing barrel is provided with a hole. The reamer is a rectangular column reamer without edges and corners. There are three reamers. The scrapers and reamers are arranged in the mixing barrel from top to bottom in the order of a scraper, a first reamer, a second reamer and a third reamer. The third reamer is arranged at the bottom of the mixing barrel. The first reamer, the second reamer and the third reamer are respectively arranged on different nested shafts of a coaxial nested rotating shaft. The first reamer and the third reamer have the same rotation direction, and the second reamer has an opposite rotation direction to the first reamer and the second reamer. The spray device is located above the mixing barrel; the barrel wall hole shielding plate is located on the inner wall of the side of the mixing barrel; The grinding unit includes a grinding machine barrel, a grinding disc, a grinding disc fixing device and a material receiving bin. The grinding disc fixing device is located above the grinding disc and is used to fix the grinding disc. The grinding disc and the grinding disc fixing device are both located in the grinding machine barrel. The material outlet of the grinding machine barrel is communicated with the material receiving bin. The grinding disc fixing device is provided with a heating device.

2. The mixing device according to claim 1, characterized in that The scraper and the reamer both rotate around a straight line perpendicular to the bottom surface of the mixing barrel as an axis.

3. The mixing device according to claim 1, characterized in that The length of the reamer is consistent with the inner radius of the mixing barrel.

4. The mixing device according to claim 1, characterized in that The reamer is a metal blade.

5. The mixing device according to claim 1, characterized in that The scraper is a polytetrafluoroethylene blade.

6. The mixing device according to claim 1, characterized in that The barrel wall of the mixing barrel is a double-layer structure, and a hole is provided on the inner side barrel wall. The bottom of the mixing barrel is provided with a discharge port, and the discharge port is communicated with the gap between the inner and outer barrel walls in the double-layer structure of the barrel wall.

7. The mixing device according to claim 1, characterized in that The grinding disc is made of zirconium oxide-plated 310 stainless steel.

8. The mixing device according to claim 1, characterized in that The pores of the grinding disc are in the shape of an inwardly concave cone.

9. The mixing device according to claim 1, characterized in that The grinding disc fixing device is made of stainless steel.

10. The mixing device according to claim 1, characterized in that The grinding cylinder is located in a receiving bin.

11. The mixing device according to claim 1, characterized in that A gap is provided at the bottom of the grinding cylinder.

12. The mixing device according to claim 1, characterized in that The material receiving bin is connected to the particle size tester.

13. The mixing device according to claim 1, characterized in that The mixing barrel is arranged on a telescopic rod.

14. The mixing device according to claim 1, characterized in that The mixing device also includes a control panel.

15. A method for mixing high specific surface area materials, characterized in that: The mixing method uses the mixing device according to any one of claims 1 to 14, comprising the following steps: The holes on the side inner wall of the mixing barrel are covered with a barrel hole shield, and the high specific surface area material and the ligand are added to the mixing barrel. The reamer is rotated at a first speed to pre-mix the powder; the pre-mixed powder is sprayed on the pre-mixed powder, and the reamer is rotated at a second speed, and the scraper is rotated to mix the materials; after mixing, the barrel hole shield is moved to expose the holes on the side inner wall of the mixing barrel, and granulation is carried out; the granulated product enters the grinding barrel and is ground on a preheated grinding disc. The ground product enters the material receiving bin to obtain the mixed powder; Wherein, the second speed is greater than the first speed.

16. The mixing method according to claim 15, characterized in that The high specific surface area material includes nanocarbon material.

17. The mixing method according to claim 16, characterized in that The nano-carbon material includes graphene and / or carbon nanotubes.

18. The mixing method according to claim 15, characterized in that The first rotation speed is 20-50 r / min.

19. The mixing method according to claim 15, characterized in that The spraying medium includes any one of ethanol, ethylene glycol or water, or a combination of at least two of them.

20. The mixing method according to claim 15, characterized in that The second rotation speed is 300-1000 r / min.

21. The mixing method according to claim 15, characterized in that The rotating speed of the scraper is 1-30 r / min.

22. The mixing method according to claim 15, characterized in that The material mixing time is 5-180 minutes.

23. The mixing method according to claim 15, characterized in that The preheating temperature is above the boiling point of the spraying medium.

24. The mixing method according to claim 15, characterized in that The mixing method further comprises blowing the ground product in the receiving bin into a particle size tester using a protective gas beam for online particle size testing.

25. The mixing method according to claim 15, wherein The mixing method comprises the following steps: Use the barrel wall hole shielding plate to cover the holes on the side inner wall of the mixing barrel, add the high specific surface area material and the ligand into the mixing barrel, rotate the reamer at a speed of 20-50r / min to premix the powder; spray on the premixed powder, rotate the reamer at a speed of 300-1000r / min, and rotate the scraper at a speed of 1-30r / min to mix the materials for 5-180min; after mixing, move the barrel wall hole shielding plate to expose the holes on the side inner wall of the mixing barrel for granulation; the granulated product enters the grinding machine barrel and is ground on the preheated grinding disc. The ground product enters the receiving bin to obtain the mixed powder. At the same time, a protective gas beam is used to blow the ground product in the receiving bin into the particle size tester for online particle size testing.

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