CN114618544B - Method for synthesizing catalyst with lamellar structure - Google Patents
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Abstract
The invention belongs to the technical field of catalysts, and relates to a synthesis method of a catalyst with a lamellar structure, which comprises the following steps: stirring 1.7-2 g of cobalt nitrate hexahydrate, 15.4g of magnesium nitrate hexahydrate, 5.6-10 g of aluminum nitrate nonahydrate, 85-97 g of urea and 470g of water to fully dissolve solids, adding the materials into a high-pressure reaction kettle, stirring and reacting for 8 hours at 120 ℃, stopping stirring, keeping the temperature and standing for 12 hours, cooling to room temperature, taking out the materials, and washing the materials until the pH is neutral; and (5) centrifugally dewatering, taking solid, drying, grinding and crushing to obtain the catalyst with the lamellar structure. The catalyst prepared by the method is used for preparing the carbon nano tube, the yield of the carbon nano tube per weight of the catalyst is not lower than 17%, the slurry ratio of the collected carbon nano tube product to the collected carbon nano tube product is 97.5% NMP+2% CNT+0.25% dispersant+0.5% PVP, the test coating ratio is 7.5g slurry+50 g HSV+15.6g LCO, the addition amount of the CNT is 0.3%, and the measured coating resistivity is not higher than 13.26mΩ.cm.
Description
Technical Field
The invention relates to a synthesis method of a catalyst with a lamellar structure, and belongs to the technical field of catalysts.
Background
In recent years, carbon nanotubes have been widely used in the lithium battery industry of new energy automobiles as an excellent conductive agent. Because the electrode has ultrahigh length-diameter ratio and high conductivity, compared with the traditional conductive agent graphite and superP, the electrode can be provided with a high-efficiency three-dimensional conductive network structure in the electrode with a small addition amount, the conductive efficiency is extremely high, and key indexes such as battery energy density, service life and the like can be improved. Therefore, the synthesis of novel carbon nanotube conductive agents to replace conventional conductive agents has been a trend.
In the synthesis process of the carbon nanotubes, the catalyst is indispensable, and the structural morphology of the catalyst influences the structure and the properties of the carbon nanotubes. The existing catalyst for synthesizing the carbon nano tubes is mainly in a disordered and piled powder state or granular state, and the synthesized carbon nano tubes are mutually agglomerated and wound, so that the defects are obvious, the subsequent dispersion and processing become difficult, and the performance of the carbon nano tubes is not facilitated. By adjusting the microstructure of the catalyst, array carbon nanotubes with consistent orientation and parallel arrangement can be synthesized under certain conditions. Compared with the wound carbon nanotubes, the array carbon nanotubes have consistent length-diameter ratio, better orientation and higher purity, and are beneficial to exerting the excellent performance of the carbon nanotubes.
In the process of synthesizing the array carbon nano tube, the problem of winding of the carbon nano tube is improved along with the application of the catalyst with a layered structure. However, the existing catalyst with a layered structure generally takes natural vermiculite raw materials as a main material, and more impurity ions such as iron, chromium and the like are introduced in the process of synthesizing the carbon nano tube, so that the subsequent purification treatment procedures and the cost are increased.
Patent CN111495380A provides a preparation method of carbon nanotube catalyst, and specifically comprises the steps of respectively preparing catalyst containing Mg 2+ 、Al 3+ 、Co 2+ And the mixed solution A and the weak base solution B of the catalyst auxiliary agent containing metal ions are added into the mixed solution A in a dropwise manner in the heating process, and then the catalyst is obtained through standing, filtering, washing and calcining. The method is used for preparing the carbon nano tube catalyst by adding urea and various weak bases as precipitants under normal pressure. However, the productivity and conductivity of the carbon nanotubes prepared by the catalyst remain to be improved.
Patent CN109665512A provides a synthesis method of multiwall carbon nanotubes, specifically comprising blending a mixed salt solution containing an active component and a carrier phase component with an alkaline solution containing an alkaline precipitant under stirring, standing at 80-105 ℃ to obtain a suspension, standing, filtering, washing, and freeze-drying to obtain a plate-like catalyst. However, the carbon nano tube prepared by the catalyst has no array orientation as can be seen from SEM characterization, and the yield and conductivity of the prepared carbon nano tube are still to be improved.
Disclosure of Invention
[ technical problem ]
The catalyst prepared by the method is used for preparing carbon nano tubes, the yield of the carbon nano tubes per weight of the catalyst is not lower than 1700%, the collected carbon nano tube product is prepared into slurry with the proportion of 97.5 percent NMP+2 percent CNT+0.25 percent dispersant+0.5 percent PVP, the test coating proportion is 7.5g slurry+50 g HSV+15.6g LCO, the addition amount of the CNT is 0.3 percent, and the measured coating resistivity is not higher than 13.26mΩ & cm.
Technical scheme
In the process of synthesizing MgAl hydrotalcite layered double hydroxide LDH, urea is used as a precipitator, and one or more active metals such as iron, cobalt, nickel and the like are loaded on an LDH laminate by utilizing the adjustable elements of the LDH laminate, so that the catalyst with the catalytic activity for catalyzing the growth of carbon nanotubes is obtained. The synthesized catalyst has a lamellar structure, and the carbon nano tube synthesized by the catalyst has array orientation and good conductivity.
The first object of the present invention is to provide a synthesis method of a catalyst with a layered structure, comprising the steps of:
stirring 1.7-2 g of cobalt nitrate hexahydrate, 15.4g of magnesium nitrate hexahydrate, 5.6-10 g of aluminum nitrate nonahydrate, 85-97 g of urea and 470g of water to fully dissolve solids, adding the materials into a high-pressure reaction kettle, stirring and reacting for 8 hours at 120 ℃, stopping stirring, keeping the temperature and standing for 12 hours, cooling to room temperature, taking out the materials, and washing the materials until the pH is neutral; and (5) centrifugally dewatering, taking solid, drying, grinding and crushing to obtain the catalyst with the lamellar structure.
A second object of the present invention is to provide a method for synthesizing a catalyst having a layered structure, comprising the steps of:
stirring 1.7g of cobalt nitrate hexahydrate, 2g of ferric nitrate hexahydrate, 15.4g of magnesium nitrate hexahydrate, 5.6g of aluminum nitrate hexahydrate, 97g of urea and 470g of water to fully dissolve solids, adding the materials into a high-pressure reaction kettle, stirring and reacting for 8 hours at 120 ℃, stopping stirring, keeping the temperature and standing for 12 hours, cooling to room temperature, taking out the materials, and washing the materials until the pH is neutral; and (5) centrifugally dewatering, taking solid, drying, grinding and crushing to obtain the catalyst with the lamellar structure.
As a preferred embodiment, the synthesis method of the catalyst with a lamellar structure comprises the following steps:
stirring 1.7g of cobalt nitrate hexahydrate, 15.4g of magnesium nitrate hexahydrate, 5.6g of aluminum nitrate nonahydrate, 97g of urea and 470g of water to fully dissolve solids, adding the materials into a high-pressure reaction kettle, stirring and reacting for 8 hours at 120 ℃, stopping stirring, keeping the temperature and standing for 12 hours, cooling to room temperature, taking out the materials, and washing the materials until the pH is neutral; and (5) centrifugally dewatering, taking solid, drying, grinding and crushing to obtain the catalyst with the lamellar structure.
As a preferred embodiment, the synthesis method of the catalyst with a lamellar structure comprises the following steps:
stirring 1.7g of cobalt nitrate hexahydrate, 15.4g of magnesium nitrate hexahydrate, 5.6g of aluminum nitrate nonahydrate, 85.9g of urea and 470g of water to fully dissolve solids, adding the materials into a high-pressure reaction kettle, stirring and reacting for 8 hours at 120 ℃, stopping stirring, keeping the temperature and standing for 12 hours, cooling to room temperature, taking out the materials, and washing the materials until the pH is neutral; and (5) centrifugally dewatering, taking solid, drying, grinding and crushing to obtain the catalyst with the lamellar structure.
As a preferred embodiment, the rotation speed of the stirring blade is set to 80-120 r/min in the high-pressure reaction kettle.
As a preferred embodiment, the drying conditions are: the solid was dried in a forced air oven at 60 ℃.
A third object of the present invention is to provide a catalyst of a lamellar structure for preparing carbon nanotubes, characterized by being prepared by the aforementioned method.
A fourth object of the present invention is to provide the use of the above-mentioned catalyst with a layered structure for preparing carbon nanotubes.
The fifth object of the present invention is to provide a method for preparing carbon nanotubes, wherein a certain weight of the catalyst with a lamellar structure is placed in a quartz tube furnace, nitrogen with a flow rate of 200ml/min is introduced, and the temperature is raised to 300 ℃ at 15 ℃/min; after the temperature reaches 300 ℃, keeping the flow rate of nitrogen unchanged, introducing hydrogen with the flow rate of 200ml/min, and continuously heating to 660 ℃ at 15 ℃/min; stopping introducing hydrogen after the temperature reaches 660 ℃, and introducing propylene with the flow rate of 100ml/min while maintaining introducing nitrogen to synthesize the carbon nano tube, wherein the reaction time is 40min; after the reaction is finished, cooling under the protection of nitrogen; after cooling, collecting the product in the tubular furnace, weighing the product, and dividing the product weight by the catalyst with a lamellar structure to calculate the yield; the yield of the carbon nano tube is not lower than 1700%.
A sixth object of the present invention is to provide the carbon nanotube prepared by the above method, wherein the carbon nanotube has an array orientation and good electrical conductivity.
In the preparation process of the catalyst, the dosage of cobalt nitrate hexahydrate, magnesium nitrate hexahydrate, aluminum nitrate nonahydrate and urea is optimized for obtaining a better LDH structure. In the reaction process, urea is selected as a precipitator, and ammonia is slowly decomposed and released at the temperature higher than 60 ℃, so that the pH value in the solution is kept constant, and simultaneously released carbon dioxide enters LDH intercalation in the form of carbonate ions. The reaction condition is a high-pressure reaction kettle, and relative high pressure is obtained at high temperature, so that the hydrotalcite compound with good dispersibility and high crystallinity is obtained compared with LDH synthesized under normal pressure. The high dispersibility of the catalytically active elements in the catalyst ensures high activity of the surface of the platelet catalyst, thereby preparing oriented carbon nanotubes.
[ beneficial effects ]:
the invention takes urea as a precipitator, and synthesizes a lamellar catalyst with high purity under high pressure condition by optimizing the dosage of cobalt nitrate hexahydrate, magnesium nitrate hexahydrate, aluminum nitrate nonahydrate and urea (see figure 1); the carbon nano tube prepared by the synthesized catalyst has array orientation (see figure 2), and has good conductivity; in the process of synthesizing the catalyst, the introduction of impurities is avoided by selecting catalyst elements, and a complex purification process is not needed in the later stage, so that the cost is reduced; the catalyst prepared by the method is used for preparing the carbon nano tube, the yield of the carbon nano tube per weight of the catalyst is not lower than 1700%, the slurry ratio of the collected carbon nano tube product to the NMP+2% CNT+0.25% dispersant+0.5% PVP is 7.5g of slurry+50 g of HSV+15.6g of LCO, the addition amount of the CNT is 0.3%, and the measured coating resistivity is not higher than 13.26mΩ & cm.
Drawings
FIG. 1 is a scanning electron microscope image of the catalysts prepared in examples 1 to 5 of the present invention at 10000 times magnification.
FIG. 2 is a scanning electron microscope image of carbon nanotubes prepared by the catalysts of examples 1 to 5 of the present invention at 10000 times magnification.
Detailed Description
Example 1
1.7g of cobalt nitrate hexahydrate, 15.4g of magnesium nitrate hexahydrate, 5.6g of aluminum nitrate nonahydrate, 85.9g of urea and 470g of pure water are weighed, stirred and dissolved, added into an autoclave, the rotation speed of a stirring blade is set to 100r/min, and the temperature is increased to 120 ℃ by electric heating, and the reaction is carried out for 8 hours at constant temperature. Stopping stirring after the reaction is finished, and keeping the temperature for 12 hours. And then cooling to room temperature, taking out the materials, and washing with water until the pH is neutral. And then centrifugally dehydrating, putting into a blast drying box, setting at 60 ℃, drying, grinding and crushing to obtain the lamellar catalyst.
Example 2
With reference to example 1, the only difference is that 1.7g of cobalt nitrate hexahydrate is replaced with 2g of ferric nitrate nonahydrate, specifically:
2g of ferric nitrate hexahydrate, 15.4g of magnesium nitrate hexahydrate, 5.6g of aluminum nitrate hexahydrate, 85.9g of urea and 470g of pure water are weighed, stirred and dissolved. Adding the mixture into an autoclave, setting the rotating speed of a stirring blade to be 100r/min, heating the mixture to 120 ℃ by electric heating, and reacting the mixture at constant temperature for 8 hours. Stopping stirring after the reaction is finished, and keeping the temperature for 12 hours. And then cooling to room temperature, taking out the materials, and washing with water until the pH is neutral. And then centrifugally dehydrating, putting into a blast drying box, setting at 60 ℃, drying, grinding and crushing to obtain the lamellar catalyst.
Example 3
With reference to example 1, the only difference is that 1.7g of cobalt nitrate hexahydrate is replaced by 1.7g of cobalt nitrate hexahydrate and 2g of ferric nitrate nonahydrate, the amount of urea is adjusted to 97g, specifically:
1.7g of cobalt nitrate hexahydrate, 2g of ferric nitrate hexahydrate, 15.4g of magnesium nitrate hexahydrate, 5.6g of aluminum nitrate hexahydrate, 97g of urea and 470g of pure water are weighed, stirred and dissolved. Adding the mixture into an autoclave, setting the rotating speed of a stirring blade to be 100r/min, heating the mixture to 120 ℃ by electric heating, and reacting the mixture at constant temperature for 8 hours. Stopping stirring after the reaction is finished, and keeping the temperature for 12 hours. And then cooling to room temperature, taking out the materials, and washing with water until the pH is neutral. And then centrifugally dehydrating, putting into a blast drying box, setting at 60 ℃, drying, grinding and crushing to obtain the lamellar catalyst.
Example 4
With reference to example 1, the only difference is that the amount of urea is adjusted to 97g, specifically:
1.7g of cobalt nitrate hexahydrate, 15.4g of magnesium nitrate hexahydrate, 5.6g of aluminum nitrate nonahydrate, 97g of urea and 470g of pure water are weighed, stirred and dissolved. Adding the mixture into an autoclave, setting the rotating speed of a stirring blade to be 100r/min, heating the mixture to 120 ℃ by electric heating, and reacting the mixture at constant temperature for 8 hours. Stopping stirring after the reaction is finished, and keeping the temperature for 12 hours. And then cooling to room temperature, taking out the materials, and washing with water until the pH is neutral. And then centrifugally dehydrating, putting into a blast drying box, setting at 60 ℃, drying, grinding and crushing to obtain the lamellar catalyst.
Example 5
Referring to example 4, only the difference was that the amount of aluminum nitrate nonahydrate was adjusted to 10g, specifically:
1.7g of cobalt nitrate hexahydrate, 15.4g of magnesium nitrate hexahydrate, 10g of aluminum nitrate nonahydrate, 97g of urea and 470g of pure water are weighed, stirred and dissolved. Adding the mixture into an autoclave, setting the rotating speed of a stirring blade to be 100r/min, heating the mixture to 120 ℃ by electric heating, and reacting the mixture at constant temperature for 8 hours. Stopping stirring after the reaction is finished, and keeping the temperature for 12 hours. And then cooling to room temperature, taking out the materials, and washing with water until the pH is neutral. And then centrifugally dehydrating, putting into a blast drying box, setting at 60 ℃, drying, grinding and crushing to obtain the lamellar catalyst.
Comparative example 1:
according to the preparation method provided in patent CN111495380a, a catalyst is prepared: 9.60 g of cobalt nitrate hexahydrate, 25.38 g of magnesium nitrate hexahydrate, 24.76 g of aluminum nitrate nonahydrate and 1.26 g of yttrium nitrate hexahydrate were weighed out and added to 400 g of pure water, which was designated as solution A. 20.73 g of potassium carbonate and 42 g of sodium bicarbonate were weighed out and dissolved in 600 g of water and designated as solution B. Solution B was slowly added dropwise to salt solution A at 100deg.C for 10h, with a final pH of 9.5. And (3) continuously preserving heat for 10 hours at 95 ℃, and then carrying out suction filtration and washing until the pH value of the washing liquid is less than 8, so as to prepare the catalyst precursor. Drying the prepared catalyst precursor at 200 ℃, then placing the dried catalyst precursor in a high-temperature furnace, rising to 900 ℃ at the speed of 15 ℃/min, and preserving heat for 1 hour to obtain the catalyst.
Comparative example 2:
according to the preparation method provided in patent CN109665512a, a catalyst is prepared: 0.84 g of cobalt nitrate hexahydrate, 10.11 g of magnesium nitrate hexahydrate, 29.59 g of aluminum nitrate nonahydrate and 11.63 g of ferric nitrate nonahydrate were weighed out and added to 500 g of pure water to be referred to as solution A. 135 g of urea was weighed and dissolved in 225mL of water and recorded as solution B, the A, B solution was mixed at room temperature, and the temperature was slowly raised to 103℃at a rate of 3℃per minute while stirring, and the reaction was stopped after continuing to keep the temperature and stirring for 12 hours. The resulting suspension was placed in an oven at 95 ℃ for 12 hours, then cooled and filtered, washed 3 times with deionized water, and freeze-dried to obtain a catalyst.
Comparative example 3:
based on example 1, only the amount of magnesium nitrate hexahydrate was changed, specifically as follows:
1.7g of cobalt nitrate hexahydrate, 25g of magnesium nitrate hexahydrate, 5.6g of aluminum nitrate nonahydrate, 85.9g of urea and 470g of pure water are weighed, stirred and dissolved, added into an autoclave, the rotation speed of a stirring blade is set to 100r/min, and the temperature is increased to 120 ℃ by electric heating, and the reaction is carried out for 8 hours at constant temperature. Stopping stirring after the reaction is finished, and keeping the temperature for 12 hours. And then cooling to room temperature, taking out the materials, and washing with water until the pH is neutral. And then centrifugally dehydrating, putting into a blast drying box, setting at 60 ℃, drying, grinding and crushing to obtain the lamellar catalyst.
Comparative example 4:
on the basis of example 1, only the reaction temperature was changed, specifically as follows:
1.7g of cobalt nitrate hexahydrate, 15.4g of magnesium nitrate hexahydrate, 5.6g of aluminum nitrate nonahydrate, 85.9g of urea and 470g of pure water are weighed, stirred and dissolved, added into an autoclave, the rotation speed of a stirring blade is set to 100r/min, and the temperature is increased to 90 ℃ by electric heating, and the reaction is carried out for 8 hours at constant temperature. Stopping stirring after the reaction is finished, and keeping the temperature for 12 hours. And then cooling to room temperature, taking out the materials, and washing with water until the pH is neutral. And then centrifugally dehydrating, putting into a blast drying box, setting at 60 ℃, drying, grinding and crushing to obtain the lamellar catalyst.
Application of catalyst in preparation of carbon nano tube
0.4g of each of the catalysts of examples 1 to 5 and comparative examples 1 to 4 was placed in a quartz tube furnace having a diameter of 60mm, nitrogen was introduced at a flow rate of 200ml/min, and the temperature was raised to 300℃at 15℃per minute. After the temperature reaches 300 ℃, keeping the flow rate of nitrogen unchanged, introducing hydrogen with the flow rate of 200ml/min, and continuously heating to 660 ℃ at 15 ℃/min; stopping introducing hydrogen, introducing propylene while maintaining the flow rate of 100ml/min, and performing carbon nanotube growth for 40min. And after the reaction is finished, cooling under the protection of nitrogen, collecting the product in the tubular furnace after cooling, weighing the product, and calculating the yield by dividing the weight of the product by the weight of the catalyst.
The collected carbon nanotube product is prepared into slurry with the ratio of 97.5 percent NMP, 2 percent CNT, 0.25 percent dispersant and 0.5 percent PVP, 7.5g slurry, 50g HSV, 15.6g LCO are tested, the addition amount of the CNT is 0.3 percent, and the test result of the measured coating resistivity is shown in the following table:
TABLE 1 productivity and coating resistivity of carbon nanotubes prepared by the catalysts of examples 1 to 4 and comparative examples 1 to 4
| Catalyst | Yield/% | Coating resistivity/mΩ.cm |
| Example 1 | 2025 | 13.05 |
| Example 2 | 1821 | 13.26 |
| Example 3 | 1700 | 12.11 |
| Example 4 | 1867 | 9.68 |
| Example 5 | 1800 | 13.25 |
| Comparative example 1 | 1350 | 22.23 |
| Comparative example 2 | 1120 | 28.16 |
| Comparative example 3 | 1070 | 18.22 |
| Comparative example 4 | 963 | 21.30 |
Comparative example 1 (catalyst prepared according to the method disclosed in patent CN111495380 a) the prepared carbon tubes were lower in productivity and poorer in conductivity (high coating resistivity) than examples 1 to 5.
The carbon tube prepared in comparative example 2 (catalyst prepared according to the method disclosed in CN109665512 a) has lower productivity and inferior conductivity than the carbon tube prepared in comparative example 2.
Comparative example 3, in which the amount of magnesium nitrate hexahydrate was changed based on example 1, the yield was decreased and the resistivity was increased as compared with example 1.
Comparative example 4, in which the reaction temperature was changed based on example 1, the yield was decreased and the resistivity was increased as compared with example 1.
Claims (6)
1. A method for preparing carbon nano tube is characterized in that a catalyst with a lamellar structure is taken and placed in a quartz tube furnace, nitrogen with the flow rate of 200ml/min is introduced, and the temperature is raised to 300 ℃ at 15 ℃/min; after the temperature reaches 300 ℃, keeping the flow rate of nitrogen unchanged, introducing hydrogen with the flow rate of 200ml/min, and continuously heating to 660 ℃ at 15 ℃/min; stopping introducing hydrogen after the temperature reaches 660 ℃, and introducing propylene with the flow rate of 100ml/min while maintaining introducing nitrogen to synthesize the carbon nano tube, wherein the reaction time is 40min; after the reaction is finished, cooling under the protection of nitrogen; after cooling, collecting the product in the tubular furnace, weighing the product, and calculating the yield by dividing the product weight by the weight of the lamellar structure catalyst; the yield of the carbon nano tube is not lower than 1700%;
the synthesis of the lamellar structure catalyst comprises the following steps: stirring 1.7-2 g of cobalt nitrate hexahydrate, 15.4-g magnesium nitrate hexahydrate, 5.6-10 g of aluminum nitrate nonahydrate, 85-97 g of urea and 470-g water to fully dissolve solids, adding the materials into a high-pressure reaction kettle, stirring and reacting for 8 hours at 120 ℃, stopping stirring, keeping the temperature and standing for 12 hours, cooling to room temperature, taking out the materials, and washing the materials until the pH is neutral; and (5) centrifugally dewatering, taking solid, drying, grinding and crushing to obtain the catalyst with the lamellar structure.
2. The method according to claim 1, wherein the synthesis of the layered catalyst comprises the steps of:
stirring 1.7g cobalt nitrate hexahydrate, 2g ferric nitrate hexahydrate, 15.4g magnesium nitrate hexahydrate, 5.6g aluminum nitrate hexahydrate, 97g urea and 470g water to fully dissolve solids, adding the materials into a high-pressure reaction kettle, stirring at 120 ℃ for reaction for 8 hours, stopping stirring, keeping the temperature and standing for 12 hours, cooling to room temperature, taking out the materials, and washing the materials until the pH is neutral; and (5) centrifugally dewatering, taking solid, drying, grinding and crushing to obtain the catalyst with the lamellar structure.
3. The method according to claim 1, wherein the synthesis of the layered catalyst comprises the steps of:
stirring 1.7g cobalt nitrate hexahydrate, 15.4g magnesium nitrate hexahydrate, 5.6g aluminum nitrate hexahydrate, 97g urea and 470g water to fully dissolve solids, adding the materials into a high-pressure reaction kettle, stirring at 120 ℃ for reaction for 8 hours, stopping stirring, keeping the temperature for 12 hours, cooling to room temperature, taking out the materials, and washing the materials until the pH is neutral; and (5) centrifugally dewatering, taking solid, drying, grinding and crushing to obtain the catalyst with the lamellar structure.
4. The method according to claim 1, wherein the synthesis of the layered catalyst comprises the steps of:
stirring 1.7g cobalt nitrate hexahydrate, 15.4g magnesium nitrate hexahydrate, 5.6g aluminum nitrate hexahydrate, 85.9g urea and 470g water to fully dissolve solids, adding the materials into a high-pressure reaction kettle, stirring and reacting for 8 hours at 120 ℃, stopping stirring, keeping the temperature and standing for 12 hours, cooling to room temperature, taking out the materials, and washing the materials until the pH is neutral; and (5) centrifugally dewatering, taking solid, drying, grinding and crushing to obtain the catalyst with the lamellar structure.
5. The method according to any one of claims 1 to 4, wherein the rotation speed of the stirring blade is set to 80 to 120r/min in the autoclave.
6. The method according to any one of claims 1 to 4, wherein the drying conditions are: the solid was dried in a forced air oven at 60 ℃.
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| CN109626357A (en) * | 2019-01-31 | 2019-04-16 | 新奥石墨烯技术有限公司 | A kind of ultra-fine carbon nanotube and preparation method thereof |
| CN111495380A (en) * | 2019-01-31 | 2020-08-07 | 江苏天奈科技股份有限公司 | Preparation method of carbon nanotube catalyst and carbon nanotube |
| CN111495381A (en) * | 2019-01-31 | 2020-08-07 | 新奥石墨烯技术有限公司 | Preparation method of flaky catalyst, flaky catalyst and application of flaky catalyst in preparation of superfine carbon nano tube |
| CN114029047A (en) * | 2021-12-22 | 2022-02-11 | 长沙晟天新材料有限公司 | Preparation method of array carbon nanotube supported catalyst |
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