CN115010116A - Method for preparing high-purity carbon nano tube from coal - Google Patents
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Abstract
The invention discloses a method for preparing high-purity carbon nanotubes by coal, which comprises the steps of activating coal particles to prepare activated coal particles, preparing coal-based carbon nanotubes by the activated coal particles and purifying the coal-based carbon nanotubes. The preparation method of the coal-based carbon nano tube is carried out in CH 4 And CO 2 In the atmosphere, by dynamically adjusting CH 4 And CO 2 The preparation process is controlled by the proportion of the carbon nano tube, so that the growth or purification process of the carbon nano tube is more continuous. In addition, the method of the invention fully utilizes the resources of coal and CO2, and provides a new method for energy conservation and emission reduction and high-value utilization of low-carbon resources.
Description
Technical Field
The invention belongs to the technical field of carbon materials, and particularly relates to a method for preparing a high-purity carbon nano tube from coal.
Background
China is the first major coal producing country in the world, coal is the main energy of China, under the constraint of current resources and environments, the coal industry of China can never only utilize the energy attribute of coal, and under the dual-carbon environment, the traditional extensive development mode needs to be changed urgently, so that the utilization efficiency of coal resources is improved.
Carbon nanotubes are tubular carbon molecules having excellent mechanical, electromagnetic, optical and thermodynamic properties and are widely used in various fields. The main methods for preparing carbon nanotubes include arc discharge, laser evaporation, plasma and chemical vapor deposition. Nowadays, how to produce carbon nanotubes more efficiently and at lower cost becomes a matter of great concern. The existing industrialized mass production technology of the carbon nano tube is mainly completed by a vapor deposition method, and coal and pyrolysis products thereof can be used as carbon sources in the growth process of the carbon nano tube, so that the carbon nano tube can be prepared by taking the coal as a raw material.
Chinese patent CN112723340A discloses a method for preparing carbon nanotubes by modulating low-rank coal, which uses subcritical H as raw material 2 The O-CO system modulates the structure of the low-rank coal to obtain modified coal, then the modified coal is subjected to catalytic pyrolysis under normal pressure to prepare the carbon nano tubes, and finally the carbon nano tubes are subjected to acid washing and ultrasonic separation. The catalyst is nano CaCO 3 、Na 2 CO 3 A mixture of one or more of CaO or KOH. The method uses long flame coal as a raw material, obtains the carbon nano tube by modifying coal through a reaction kettle, obtains the pure carbon nano tube by acid washing and ultrasonic oscillation, but needs a subcritical system for modifying coal, has higher requirements on the temperature and the pressure of equipment, requires the pressure and the temperature in the reaction kettle and also requires air isolation and ultrasonic separation, and compared with the method adopting a CO supercritical system, the method adopts a low-temperature and low-pressure carbon dioxide supercritical system to carry out a purification process because CO and water can obtain active H under the supercritical system.
Chinese patent CN113955742A discloses a process for preparing carbon nanotubes by carbon dioxide-methane reforming technology, which takes methane and carbon dioxide as carbon sources, makes full use of greenhouse gases (carbon dioxide and methane) as raw materials to the utmost extent, prepares carbon nanotubes and synthesis gas with high added value, and solves the problem of low utilization rate of raw materials in the preparation process of carbon nanotubes. In contrast, the method is completed by adjusting the proportion of the carbon dioxide gas introduced into the methane and the carbon dioxide gas, when the proportion of the carbon dioxide gas is higher, the carbon nanotube purification process is performed, the carbon deposition is eliminated, and when the proportion of the carbon dioxide gas is lower, the carbon nanotube preparation process is performed in a large scale, and a large amount of carbon deposition is generated; if 2 processes are circulated, carbon deposition can be effectively reduced, and the growth of the carbon nano tube is promoted.
Chinese patent CN108514872A discloses a preparation method for carbon nanotube alkali metal catalyst, which comprises the steps of firstly preparing KOH or NaOH alkali solution, then soaking a catalyst carrier in the KOH or NaOH alkali solution, stirring and soaking in a magnetic stirrer for 4-24h, placing solid residue in an oven with the temperature of 100-105 ℃ for drying for 6-15h after suction filtration, and finally roasting at high temperature to obtain the carbon nanotube alkali metal catalyst. The main components of the carbon nano tube alkali metal catalyst obtained by the method are KOH and NaOH, while the potassium hydrogen acid catalyst is used as a hydroxyl corrosion inhibitor and provides an alkaline environment to promote the catalysis of K ions, so that a compound similar to KOH is obtained at a high temperature compared with the hydroxyl generated at a high temperature, and the inactivation caused by the combination of the KOH catalyst and carbon dioxide at a low temperature is avoided.
It can be seen from the published documents that the carbon nanotube product prepared by the prior art method contains more carbon deposit and residual tar impurities, and has lower purity and poorer oxidation resistance, so that an efficient, simple and low-cost method for preparing high-purity coal-made carbon nanotubes is urgently needed.
Disclosure of Invention
The invention aims to provide a method for preparing carbon nanotubes by coal. The mass and volume of the particles of the present invention are expressed in parts. The invention adopts the following technical scheme.
A method for preparing carbon nanotubes by coal comprises the following steps:
the first step is as follows: anthracite is selected, crushed and screened to obtain coal particles with the particle size of 0.1-10.0 nm;
the second step: selecting 50-80 parts of the coal particles obtained in the step one and 20-60 parts of an activating agent to mix, putting the mixture into a high-temperature tube furnace, raising the temperature to 900- -1 Introducing carbon dioxide for activating for 1-5 h;
the third step: selecting 30-60 parts of the activated coal particles obtained in the second step, and loading potassium bicarbonate on the activated coal particles to obtain a mixture, wherein the mass part ratio of the potassium bicarbonate to the activated coal particles is 1: 1-3; the mixture is put into a first carbon nano tube preparation reactor with the space velocity of 8000- -1 Introducing a mixture of 1:1, heating the mixed gas of methane and carbon monoxide to 850-950 ℃ at the speed of 3-5 ℃/min, and keeping the temperature for 3-5h at the temperature to realize the nucleation and growth of the carbon nano tube, thereby preparing the coal-based carbon nano tube A containing impurities such as carbon black, carbon deposition and the like;
the fourth step: the coal-based carbon nano tube A obtained in the third step is selected to be placed in a second carbon nano tube preparation reactor with the temperature being stabilized at 800- -1 Introducing mixed gas of methane and carbon dioxide, keeping for 4-6h, performing methane and carbon dioxide reforming reaction purification and preparing carbon nano tube E, and obtaining mixed gas products mainly comprising carbon monoxide and hydrogen;
the fifth step: selecting 30-50 parts of the coal-based carbon nanotube B obtained in the fourth step, placing the coal-based carbon nanotube B into a carbon dioxide supercritical fluid with the temperature of 31-34 ℃ and the pressure of 7.38-8.05MPa, and maintaining the pressure for 1-3h to eliminate carbon black, carbon deposit and partial residual tar in the coal-based carbon nanotube B, so as to obtain a relatively pure coal-based carbon nanotube C;
and a sixth step: and (4) repeating the processes of the fourth step and the fifth step for 1-5 times to obtain coal-based carbon nanotubes D, then soaking 20-40 parts of the coal-based carbon nanotubes D in 50-100 parts of hydrogen-supplying and antioxidant solvents according to the mass part ratio, and then washing with 20-60 parts of hydrochloric acid solution to finally obtain the coal-based carbon nanotubes E with the purity of more than or equal to 40%.
Preferably, the activation treatment is carried out in a high-temperature tube furnace50-80 parts of coal particles and 20-60 parts of activating agent mixture, raising the temperature to 900- -1 Introducing carbon dioxide to activate for 1-5 h; the activating agent is composed of 5-20 parts of KOH and 5-10 parts of K 2 CO 3 And 90-120 parts of distilled water are uniformly mixed and stirred until the mixture is completely dissolved to obtain the water-soluble organic fertilizer.
Preferably, the carbon nanotube growth catalyst is potassium bicarbonate, and the mass part ratio of the carbon nanotube growth catalyst to the activated coal particles is 1: 1-3.
Preferably, the activated coal particles supported by the carbon nanotube growth catalyst are subjected to an isometric impregnation method.
Preferably, the mixed gas of methane and carbon monoxide with the gas volume ratio of 1:1 is introduced into the step three, and the gas space velocity is 8000- -1 (ii) a And keeping the temperature of the mixture C in the carbon nano tube preparation reactor for 3-5h to obtain the coal-based carbon nano tube A.
Preferably, the coal-based carbon nanotube A obtained in the third step is stabilized in the carbon nanotube preparation reactor at the temperature of 800- -1 And the volume ratio of methane to carbon dioxide in the mixed gas is 3:1-4, and the temperature is kept constant for 4-6h to obtain the primarily purified carbon nano tube B.
Preferably, in the fifth step, the temperature of the carbon dioxide supercritical fluid is 31-34 ℃, and the pressure is 7.38-8.05 MPa.
Preferably, in the seventh step, the hydrogen donor and antioxidant solvent is a mixture of ethanol and isopropanol, the mass portion ratio of ethanol to isopropanol is 1:0.2-0.6, and the concentration of the hydrochloric acid solution is 5% -20%.
Compared with the prior art, the invention has the beneficial effects that:
(1) the preparation method of the coal-based carbon nano tube firstly converts anthracite particles into microporous activated coal particles, and KOH and K are adopted in the process 2 CO 3 The two activators synergistically change the chemical compositions of oxygen-containing functional groups and pore structures on the surface of coal, so that bonds between carbon atoms and hetero atoms in coal heterocyclic compound molecules are easy to crackThen the polymerization or polycondensation reaction is carried out to obtain the activated coal particles with rich micropore structures. The activated coal particles with rich microporous structures are used as raw materials for preparing the coal-based carbon nano tubes, so that adsorption and dispersion of K ions on the surfaces of micropores as catalysts are facilitated, and uniform dispersion of the K ion catalysts is ensured. Meanwhile, the micromolecular volatile matters released in the catalysis process are beneficial to reducing the poisoning of the catalyst and the generation of carbon deposition, reducing the deposition of coal tar and carbon deposition impurities in the carbon nano tube and promoting the growth of more carbon nano tubes on the substrate with the micropore structure of the activated coal.
(2) In the method, a potassium bicarbonate catalyst is added as a hydroxyl corrosion inhibitor and an alkaline environment is provided to promote the catalytic action of K ions, and the activated coal particles nucleate and grow under the action of the potassium bicarbonate catalyst and under the high-temperature alkaline condition of a methane and carbon monoxide mixed gas atmosphere with a certain airspeed to generate the coal-based carbon nanotube containing impurities such as carbon black, carbon deposition and the like. Then in CH 4 And CO 2 Under the mixed gas atmosphere, by adjusting CH 4 And CO 2 The growth process of the coal-based carbon nano tube is dynamically adjusted according to the proportion of the carbon nano tube and the carbon black, so that the carbon nano tube grows directionally, and the generation of carbon deposition and carbon black can be further reduced.
(3) In the method of the invention, the supercritical CO with low temperature and high pressure is adopted 2 The system treats the coal-based carbon nanotube intermediate product, and has the functions of eliminating carbon black, carbon deposit and partial residual tar in the coal-based carbon nanotube and carbon black, carbon deposit and tar attached to the surface of the catalyst, and increasing the CO content of the porous coal-based carbon nanotube intermediate product 2 The physical adsorption of the carbon nano tube promotes the continuous growth of the carbon nano tube, thereby increasing the yield and the product purity of the carbon nano tube. Relative to CO-H 2 O、CO 2 -H 2 And by adopting supercritical technologies such as O and the like, the temperature requirement of the supercritical process of carbon dioxide is low, the pressure condition at low temperature is better controlled, and part of impurities affecting the catalytic activity can be removed more efficiently.
(4) In the method, the obtained coal-based carbon nano tube is treated by the hydrogen supply solvent, oxygen-containing functional groups on the surface of the carbon nano tube can be reduced, the surface is smoother, the antioxidation performance of the carbon nano tube can be improved by using the antioxidation solvent for immersion treatment, and finally, the oxygen-containing functional groups on the surface which are not completely separated in the treatment process can be eliminated by using hydrochloric acid treatment, so that a large amount of high-purity carbon nano tube products with good antioxidation performance can be obtained.
Drawings
FIG. 1 is a flow chart of the carbon nanotube preparation process of the present invention.
FIG. 2 is an SEM representation of the carbon nanotubes prepared in example 1 of the present invention, and it can be seen that this scheme produces a large number of carbon nanotubes and is relatively ordered and smooth overall.
Detailed Description
For a more detailed understanding of the technical content, features and effects of the present invention, reference is now made to the accompanying drawings and examples, which are set forth in the following description.
Example 1.
A method for preparing carbon nanotubes by coal is characterized by comprising the following steps: the method comprises the following steps:
the first step is as follows: anthracite is selected, crushed and screened to obtain coal particles with the particle size of 0.1-10.0 nm;
the second step is that: selecting 50 parts of coal particles obtained in the step one and 20 parts of activating agent (5 parts of KOH and 5 parts of K used as the activating agent) 2 CO 3 Mixing with 90 parts of distilled water completely, placing into a beaker, stirring uniformly until the mixture is completely dissolved), placing into a high-temperature tube furnace, heating to 900 ℃ at a heating rate of 3 ℃, stabilizing the temperature for 1h, and then at an airspeed of 8000h -1 Introducing carbon dioxide to activate for 2 h;
the third step: selecting 30 parts of activated coal particles obtained in the second step, and loading potassium bicarbonate on the activated coal particles to obtain a mixture, wherein the mass part ratio of the potassium bicarbonate to the activated coal particles is 1: 1; placing the mixture into a first carbon nanotube preparation reactor at an airspeed of 8000h -1 Introducing a mixture of 1:1, heating the mixed gas of methane and carbon monoxide to 850 ℃ at the speed of 3 ℃/min, keeping the temperature constant for 3 hours at the temperature, realizing the nucleation and growth of the carbon nano tube, and preparing the coal-based carbon nano tube A containing impurities such as carbon black, carbon deposition and the like;
the fourth step: selecting the third stepThe obtained coal-based carbon nano tube A is placed in a second carbon nano tube preparation reactor with the internal temperature of 800 ℃ and the gas volume space velocity of 8000h -1 Introducing mixed gas with the volume ratio of methane to carbon dioxide of 3:1, keeping for 4h, performing methane-carbon dioxide reforming reaction purification and preparing carbon nano tube E, and obtaining mixed gas products mainly comprising carbon monoxide and hydrogen;
the fifth step: selecting 30 parts of the coal-based carbon nanotube B obtained in the fourth step, placing the coal-based carbon nanotube B into a carbon dioxide supercritical fluid with the temperature of 31 ℃ and the pressure of 7.38MPa, and maintaining the pressure for 1 hour to eliminate carbon black, carbon deposit and partial residual tar in the coal-based carbon nanotube B so as to obtain a relatively pure coal-based carbon nanotube C;
and a sixth step: and repeating the process of the fourth step and the process of the fifth step for 1-5 times to obtain coal-based carbon nanotubes D, then soaking 20 parts of the coal-based carbon nanotubes D by using 50 parts of a mixture of ethanol and isopropanol in a mass part ratio of 1:0.2, and then washing by using 20 parts of a hydrochloric acid solution with the concentration of 5% to finally obtain the coal-based carbon nanotubes E with the purity of 41.5%.
Example 2.
A method for preparing carbon nanotubes by coal is characterized by comprising the following steps: the method comprises the following steps:
the first step is as follows: anthracite is selected, crushed and screened to obtain coal particles with the particle size of 0.1-10.0 nm;
the second step is that: selecting 60 parts of coal particles obtained in the step one and 40 parts of activating agent (10 parts of KOH and 8 parts of K are used as the activating agent) 2 CO 3 Mixing with 100 parts of distilled water completely, placing into a beaker, stirring uniformly until the mixture is completely dissolved), placing into a high-temperature tube furnace, heating to 1000 ℃ at a heating rate of 4 ℃, stabilizing the temperature for 1h, and then keeping the space velocity at 9000h -1 Introducing carbon dioxide for activation for 3 hours;
the third step: selecting 40 parts of the activated coal particles obtained in the second step, and loading potassium bicarbonate on the activated coal particles to obtain a mixture, wherein the mass part ratio of the potassium bicarbonate to the activated coal particles is 1: 2; placing the mixture into a first carbon nanotube preparation reactor at an airspeed of 10000h -1 Introducing a mixture of 1:1, heating the mixed gas of methane and carbon monoxide to the temperature of 4 ℃/minKeeping the temperature at 900 ℃ for 4h to realize the nucleation and growth of the carbon nano tube, and preparing the coal-based carbon nano tube A containing impurities such as carbon black, carbon deposition and the like;
the fourth step: placing the coal-based carbon nano tube A obtained in the third step into a second carbon nano tube preparation reactor with the internal temperature of 900 ℃, and setting the gas volume space velocity to 10000h -1 Introducing mixed gas with the volume ratio of methane to carbon dioxide of 3:2, keeping for 5 hours, carrying out methane-carbon dioxide reforming reaction purification and preparing carbon nano tubes E, and obtaining mixed gas products mainly comprising carbon monoxide and hydrogen;
the fifth step: selecting 40 parts of the coal-based carbon nanotube B obtained in the fourth step, placing the coal-based carbon nanotube B into a carbon dioxide supercritical fluid with the temperature of 32 ℃ and the pressure of 7.60MPa, and maintaining the pressure for 2 hours to eliminate carbon black, carbon deposit and partial residual tar in the coal-based carbon nanotube B, so as to obtain a relatively pure coal-based carbon nanotube C;
and a sixth step: and repeating the fourth step and the fifth step for 1-5 times to obtain a coal-based carbon nanotube D, then soaking 30 parts of the coal-based carbon nanotube D in a mixture of ethanol and isopropanol according to the mass part ratio of 80 parts to 1:0.4, and then washing with 40 parts of 10% hydrochloric acid solution to finally obtain the coal-based carbon nanotube E with the purity of 45.5%.
Example 3.
A method for preparing carbon nanotubes by coal is characterized by comprising the following steps: the method comprises the following steps:
the first step is as follows: anthracite is selected, crushed and screened to obtain coal particles with the particle size of 0.1-10.0 nm;
the second step is that: selecting 80 parts of coal particles obtained in the step one and 60 parts of activating agent (the activating agent is prepared by using 20 parts of KOH and 10 parts of K) 2 CO 3 Mixing with 120 parts of distilled water completely, placing into a beaker, uniformly stirring until the mixture is completely dissolved), placing into a high-temperature tube furnace, heating to 1050 ℃ at a heating rate of 5 ℃, stabilizing the temperature for 2h, and then keeping the space velocity at 10000h -1 Introducing carbon dioxide to activate for 5 h;
the third step: selecting 60 parts of activated coal particles obtained in the second step, and loading potassium bicarbonate on the activated coal particles to obtain a mixture, wherein the potassium bicarbonate and the activated coal particles are equal in massThe proportion of parts is 1: 3; placing the mixture into a first carbon nanotube preparation reactor at an airspeed of 30000h -1 Introducing a mixture of 1:1, heating the mixed gas of methane and carbon monoxide to 950 ℃ at the speed of 5 ℃/min, keeping the temperature constant for 5 hours at the temperature, realizing the nucleation and growth of the carbon nano tube, and preparing the coal-based carbon nano tube A containing impurities such as carbon black, carbon deposition and the like;
the fourth step: placing the coal-based carbon nano tube A obtained in the third step into a second carbon nano tube preparation reactor with the internal temperature of 950 ℃ and stabilizing the coal-based carbon nano tube A in the carbon nano tube preparation reactor at the temperature of 950 ℃, wherein the air volume space velocity is 20000h -1 Introducing mixed gas with the volume ratio of methane to carbon dioxide being 3:4, keeping for 6h, carrying out methane carbon dioxide reforming reaction purification and preparing carbon nano tube E, and obtaining mixed gas products mainly comprising carbon monoxide and hydrogen;
the fifth step: selecting 50 parts of the coal-based carbon nanotube B obtained in the fourth step, placing the coal-based carbon nanotube B into a carbon dioxide supercritical fluid with the temperature of 34 ℃ and the pressure of 8.05MPa, and maintaining the pressure for 3 hours to eliminate carbon black, carbon deposit and partial residual tar in the coal-based carbon nanotube B, so as to obtain a relatively pure coal-based carbon nanotube C;
and a sixth step: and repeating the process of the fourth step and the process of the fifth step for 1-5 times to obtain coal-based carbon nanotubes D, then soaking 40 parts of the coal-based carbon nanotubes D by using 100 parts of a mixture of ethanol and isopropanol in a mass part ratio of 1:0.6, and then washing by using 60 parts of 20% hydrochloric acid solution to finally obtain the coal-based carbon nanotubes E with the purity of 48%.
Claims (8)
1. A method for preparing high-purity carbon nanotubes by coal is characterized by comprising the following steps: the method comprises the following steps:
the first step is as follows: selecting an anthracite sample, crushing and screening to obtain coal particles with the particle size of 0.1-10.0 nm;
the second step is that: selecting 50-80 parts of the coal particles obtained in the step one, adding 20-60 parts of an activating agent for activation treatment, and cooling to room temperature under the condition of nitrogen after activation to obtain activated coal particles;
the third step: selecting 30-60 parts of the activated coal particles obtained in the second step, and loading a carbon nano tube growth catalyst on the activated coal particles to obtain a mixture; placing the mixture into a first carbon nano tube preparation reactor, introducing mixed gas of methane and carbon monoxide at a certain airspeed, heating to 850-950 ℃ at the heating rate of 3-5 ℃/min, and keeping the temperature for a period of time to realize the nucleation and growth of the carbon nano tube to obtain a coal-based carbon nano tube A containing impurities;
the fourth step: placing the coal-based carbon nanotube A obtained in the third step in a second carbon nanotube preparation reactor with the internal temperature of 800-950 ℃, introducing mixed gas of carbon dioxide and methane and keeping for a period of time to obtain a preliminarily purified coal-based carbon nanotube B and a mixed gas product mainly containing carbon monoxide and hydrogen;
the fifth step: selecting 30-50 parts of the primarily purified coal-based carbon nanotube B obtained in the fourth step, transferring the primarily purified coal-based carbon nanotube B into a carbon dioxide supercritical fluid, and maintaining the pressure for 1-3 hours to eliminate carbon deposition and residual tar in the coal-based carbon nanotube B, so as to obtain a pure coal-based carbon nanotube C;
and a sixth step: and repeating the process of the fourth step and the process of the fifth step for 1-5 times to obtain a coal-based carbon nanotube D, then soaking 20-40 parts of the coal-based carbon nanotube D by using 50-100 parts of hydrogen supply and antioxidant solvent according to the mass part ratio, and then washing by using 20-60 parts of hydrochloric acid solution to finally obtain the coal-based carbon nanotube E with the purity of more than or equal to 40%.
2. The method for preparing high-purity carbon nanotubes from coal according to claim 1, wherein: the activation treatment in the second step is that 50-80 parts of coal particles and 20-60 parts of activating agent mixture are added into a high-temperature tube furnace, the temperature is raised to 900- -1 Introducing carbon dioxide to activate for 1-5 h; the activating agent is composed of 5-20 parts of KOH and 5-10 parts of K 2 CO 3 And 90-120 parts of distilled water are uniformly mixed and stirred until the mixture is completely dissolved to obtain the water-soluble organic fertilizer.
3. The method for preparing high-purity carbon nanotubes using coal according to claim 1, wherein: the carbon nano tube growth catalyst in the third step is potassium bicarbonate, and the mass part ratio of the carbon nano tube growth catalyst to the activated coal particles is 1: 1-3.
4. The method for preparing high-purity carbon nanotubes from coal according to claim 1, wherein: in the third step, the carbon nano tube growth catalyst load activation coal particles adopt an isometric impregnation method.
5. The method for preparing high-purity carbon nanotubes from coal according to claim 1, wherein: step three, introducing the mixed gas of methane and carbon monoxide with the gas volume ratio of 1:1, and the gas space velocity is 8000- -1 (ii) a And keeping the temperature of the mixture C in the carbon nano tube preparation reactor for 3-5h to obtain the coal-based carbon nano tube A.
6. The method for preparing high-purity carbon nanotubes from coal according to claim 1, wherein: in the fourth step, the coal-based carbon nano tube A obtained in the third step is stabilized in the carbon nano tube preparation reactor at the temperature of 800-950 ℃, and the air speed of the mixed gas of carbon dioxide and methane is 8000-20000h -1 And the volume ratio of methane to carbon dioxide in the mixed gas is 3:1-4, and the temperature is kept constant for 4-6h to obtain the primarily purified carbon nano tube B.
7. The method for preparing high-purity carbon nanotubes from coal according to claim 1, wherein: in the fifth step, the temperature of the carbon dioxide supercritical fluid is 31-34 ℃, and the pressure is 7.38-8.05 MPa.
8. The method for preparing high-purity carbon nanotubes from coal according to claim 1, wherein: in the sixth step, the hydrogen donor and antioxidant solvent is a mixture of ethanol and isopropanol, the mass part ratio of the ethanol to the isopropanol is 1:0.2-0.6, and the concentration of the hydrochloric acid solution is 5% -20%.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| KR20100082707A (en) * | 2009-01-09 | 2010-07-19 | 세종대학교산학협력단 | Method for purifying carbon nanotubes and method for dispersing carbon nanotubes |
| CN110562960A (en) * | 2019-09-05 | 2019-12-13 | 太原理工大学 | preparation and purification method of coal-based carbon nano tube |
| CN111333029A (en) * | 2020-02-29 | 2020-06-26 | 太原理工大学 | Process for reforming and reducing iron and generating carbon nano tube by methane and carbon dioxide |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| KR20100082707A (en) * | 2009-01-09 | 2010-07-19 | 세종대학교산학협력단 | Method for purifying carbon nanotubes and method for dispersing carbon nanotubes |
| CN110562960A (en) * | 2019-09-05 | 2019-12-13 | 太原理工大学 | preparation and purification method of coal-based carbon nano tube |
| CN111333029A (en) * | 2020-02-29 | 2020-06-26 | 太原理工大学 | Process for reforming and reducing iron and generating carbon nano tube by methane and carbon dioxide |
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