KR20090029956A - Apparatus and method of producting carbon nano tube - Google Patents

Abstract

A carbon nanotube manufacturing device is provided to prevent erasure of metallic catalyst by preventing metal catalyst particle of small size from being ejected through an exhaust pipe, to improve productivity and to cut down manufacturing cost. A carbon nanotube manufacturing device(100) includes: a reactor(110) providing reaction space in which the carbon nanotube is generated by reacting metallic catalyst and source gas; and a spreader plate(140) equipped in the reaction space and dispersing source gas. The reaction space is segmented into the first reaction space(RS1) having the spreader and the second reaction space(RS2) positioned on a top of the first reaction space.

Description

Carbon nanotube manufacturing apparatus and method thereof {APPARATUS AND METHOD OF PRODUCTING CARBON NANO TUBE}

The present invention relates to a carbon nanotube manufacturing apparatus and a method thereof, and more particularly, to a carbon nanotube manufacturing apparatus and method for producing carbon nanotubes by flowing metal catalyst particles.

Carbon nanotubes (CNTs) are three adjacent carbon atoms joined together in a hexagonal honeycomb pattern to form a carbon plane and the carbon plane is rolled into a cylindrical shape to form a tube.

Carbon nanotubes exhibit metallic or semiconducting conductivity depending on their structure, and can be widely applied in various technical fields. For example, carbon nanotubes are applicable to electrodes of electrochemical storage devices such as secondary batteries, fuel cells or supercapacitors, electromagnetic shielding, field emission displays, or gas sensors.

Carbon nanotubes are produced by dispersing and reacting metal catalyst particles with a hydrocarbon-based source gas in a high temperature reactor. That is, the metal catalyst reacts with the source gas while growing the carbon nanotubes while floating in the reactor by the source gas. During the production of the carbon nanotubes, the source gas is continuously injected into the reactor, and the gas in the reactor is discharged through the exhaust hole formed in the upper surface of the reactor for smooth flow of the source gas.

However, the smaller particles of the metal catalyst particles are sucked into the exhaust device through the exhaust holes before reacting with the source gas, so that the metal catalyst is lost.

An object of the present invention to provide a carbon nanotube manufacturing apparatus that can prevent the loss of the metal catalyst.

It is also an object of the present invention to provide a method for producing carbon nanotubes using the carbon nanotube manufacturing apparatus described above.

Carbon nanotube manufacturing apparatus according to one feature for realizing the above object of the present invention, the reactor and the dispersion plate.

The reactor provides a reaction space in which the metal catalyst and the source gas react with each other to generate carbon nanotubes, and a dispersion plate is provided in the reaction space to disperse the source gas. The reaction space is partitioned into a first reaction space provided with the dispersion plate and a second reaction space located above the first reaction space, and the reactor has a width corresponding to the first reaction space above the dispersion plate. It gradually widens as you go.

In addition, the reactor has a width corresponding to the second reaction space is greater than or equal to a maximum width corresponding to the first reaction space.

On the other hand, the exhaust port is located at the end of the upper surface.

Carbon nanotube manufacturing apparatus is provided adjacent to the outer wall of the reactor, and further comprises a heating unit for heating the reactor. The heating unit has a different temperature between the first region corresponding to the first reaction space and the second region corresponding to the second reaction space, and the temperature of the first region is higher than the temperature of the second region.

In addition, the carbon nanotube manufacturing method according to one feature for realizing the above object of the present invention is as follows. First, a metal catalyst and a source gas are provided inside the reactor. The source gas velocity difference between the lower region and the upper region of the reactor is increased to separate the metal catalyst according to the particle size and suspended in different regions. The source gas and the metal catalyst react to generate carbon nanotubes.

In the floating of the metal catalyst, the width of the reactor increases from the lower end to the upper end so that the relatively large metal catalyst particles are suspended in the lower region of the reactor of the source gas, and the small metal catalyst Particles are suspended in the upper region of the reactor.

According to the carbon nanotube manufacturing apparatus and method thereof according to the present invention, the lower width of the reactor is reduced, the upper width is increased to increase the source gas speed difference between the upper region and the lower region of the reactor. Accordingly, the metal catalyst particles having a relatively large particle size are suspended in the lower region of the reactor, and the metal catalyst particles having a relatively small particle size are suspended in the upper region. Therefore, the carbon nanotube manufacturing apparatus prevents the small size of the metal catalyst particles from being discharged through the exhaust port, thereby preventing the loss of the metal catalyst, reducing the manufacturing cost, and improving the productivity.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a view showing a carbon nanotube manufacturing apparatus according to an embodiment of the present invention.

Referring to FIG. 1, the apparatus for manufacturing carbon nanotubes (CNTs) according to the present invention 100 includes a reactor 110, a catalyst supply nozzle 120, a source gas line 130, a dispersion plate 140, The first and second heating units 151 and 152 and the recovery line 160 are included.

In detail, the reactor 110 includes a body 111 and a cover 112. The body portion 111 has a cylindrical shape with an upper surface opened and is made of a material resistant to heat, for example, stainless steel. The body part 111 provides a reaction space RS in which a preheating space PHS in which the source gas SG is preheated and a carbon nanotube CNT is manufactured, and the reaction space RS is formed in a first manner. It is divided into a reaction space RS1 and a second reaction space RS2 positioned above the first reaction space RS1.

The cover part 112 is provided on the body part 111. The cover part 112 is coupled to the body part 111 to seal the body part 111. The cover part 112 is provided with an exhaust port 112a for discharging the exhaust gas EG formed by the reaction of the metal catalyst MC and the source gas SG to the outside. The exhaust port 112a is connected to an exhaust device (not shown) to provide the exhaust gas EG to the exhaust device.

The exhaust port 112a is formed at an end of the upper surface of the cover part 112 to prevent the metal catalyst MC from being lost through the exhaust port 112a. That is, the flow rate of the source gas SG introduced into the reaction space RS gradually decreases from the central portion of the reaction space RS toward the side wall of the reactor 110. Therefore, since the flow velocity at the end side is relatively smaller than the center portion of the cover portion 112, the loss of the metal catalyst MC can be prevented and the exhaust gas EG can be discharged efficiently.

The body part 111 is connected to the catalyst supply nozzle 120 for providing the metal catalyst MC. An output end of the catalyst supply nozzle 120 penetrates a side wall of the body 111 and is provided in the first reaction space RS1 to provide the metal catalyst MC to the first reaction space RS1. do. Here, as the metal catalyst MC, an organometallic compound having a magnetic body, for example, iron (Fe), cobalt, nickel, or the like is used.

On the other hand, the source gas line 130 is provided below the body portion 111. In this embodiment, the carbon nanotube manufacturing apparatus 100 is provided with one source gas line 130, the number of the source gas line 130 may increase with the size of the reactor 110. have.

The source gas line 130 is coupled to the bottom surface of the body portion 111 and provides the source gas SG to the body portion 111. Here, as the source gas (SG), a hydrocarbon-based gas such as acetylene, ethylene, methane, hydrogen gas, or the like is used. The source supply hole 111a is formed on the bottom surface of the body 111 in one-to-one correspondence with the source gas line 130. The source gas SG is introduced into the preheating space PHS from the source gas line 130 through the source supply hole 111a.

On the other hand, the dispersion plate 140 is provided at the boundary between the first reaction space (RS1) and the preheating space (PHS). The dispersion plate 140 is spaced apart from the bottom surface of the body portion 111 to face the bottom surface and is disposed below the catalyst supply nozzle 120. The distribution plate 140 has a plurality of distribution holes 141 for uniformly dispersing the source gas (SG). That is, the source gas SG is introduced into the preheating space PHS from the source gas line 130, and the source gas SG introduced into the preheating space PHS is connected to the dispersion holes 141. It is dispersed in the first reaction space (RS1) through.

The metal catalyst MC introduced into the upper portion of the distribution plate 140 floats the reaction space RS by the source gas SG introduced through the distribution holes 141, and the source gas SG. React). Accordingly, the carbon nanotubes (CNT) are grown on the metal catalyst (MC).

As such, since the carbon nanotubes (CNT) are generated while the metal catalyst (MC) is suspended in the reaction space (RS), as the floating of the metal catalyst (MC) is activated, the carbon nanotubes (CNT) Growth is activated.

The degree of floating of the metal catalyst MC is adjusted according to the pressure of the source gas SG, and the source gas SG is determined according to the particle size of the metal catalyst MC. In general, the particle size of the metal catalyst (MC) is about 0.6㎛ to about 300㎛, the particle distribution is wide. Therefore, the pressure of the source gas SG is determined based on the metal catalyst particles of medium size. Accordingly, relatively small metal catalyst particles may be discharged to the exhaust port 112a by the pressure of the source gas SG.

In order to prevent this, the reactor 110 separates a region according to the particle size of the metal catalyst MC to float the metal catalyst MC.

Specifically, the body portion 111 gradually increases as the width W1 corresponding to the first reaction space RS1 moves upward from the dispersion plate 140. That is, since the sidewalls defining the first reaction space RS1 are formed to be inclined at a predetermined angle θ with respect to the ground, the body part 111 has a width of the first reaction space RS1 extending from the bottom to the top. It gradually increases as you go. In an example of the present invention, the inclination θ of the side wall defining the first reaction space RS1 is about 30 degrees to about 40 degrees with respect to the ground.

In addition, the body 111 has a width W2 corresponding to the second reaction space RS2 uniformly formed, and has a width equal to a maximum width corresponding to the first reaction space RS1.

As described above, since the width of the reaction space RS increases toward the upper portion, the pressure difference between the lower region and the upper region increases. In other words, according to Bernoulli's theorem, fluid increases in velocity through narrow passages and decreases in velocity through wide passages. Also, increasing the speed of the fluid lowers the pressure, and conversely decreasing the pressure increases the pressure.

According to Bernoulli's theorem, the pressure of the source gas SG increases as the pressure goes down toward the lower portion of the first reaction space RS1, and the second reaction space RS2 becomes the first reaction space ( The speed of the source gas SG is lower than that of RS1, so that the pressure of the source gas SG is increased. Accordingly, the large metal catalyst particles in the metal catalyst MC are suspended in the first reaction space RS1, and the small metal catalyst particles are suspended in the second reaction space RS2.

As such, the reactor 110 is separated according to the sizes of the metal catalyst particles and suspended in source gas SG of different speeds, thereby preventing the small size metal catalyst particles from being discharged through the exhaust port 112a. do.

Accordingly, the reactor 110 activates the growth of the carbon nanotubes (CNT), improves productivity, and reduces manufacturing costs.

In addition, since the lower width of the first reaction space RS1 is smaller than in the prior art, the diameter DD of the dispersion plate 140 is reduced in comparison with the prior art. Accordingly, even when the metal catalyst MC is supplied in the same amount as before, since the height of the metal catalyst layer loaded on the dispersion plate 140 increases, the expansion rate of the metal catalyst layer increases, and the gas utilization rate increases. Purity of carbon nanotubes (CNT) is improved.

Meanwhile, the first and second heating parts 151 and 152 are provided on the outer wall of the body part 111. The first and second heating units 151 and 152 heat the body 111 to maintain the temperature of the first reaction space RS1 at an appropriate temperature. Specifically, the first heating unit 151 is provided in a region corresponding to the preheating space PHS, and raises the temperature of the preheating space PHS to an appropriate temperature. As a result, the source gas SG introduced into the preheating space PHS is heated.

The second heating unit 152 is provided in a region corresponding to the reaction space RS, and maintains the temperature of the reaction space RS at an appropriate temperature for activating growth of the carbon nanotubes CNT. Let's do it. Here, since the sidewall of the first reaction space RS1 is inclined at a predetermined angle, the body part 111 has a separation distance from the second heating part 152 as it goes downward, and the second heating part ( Thermal conductivity from 152 is reduced.

In consideration of this, the second heating unit 152 has a temperature of the first region A1 corresponding to the first reaction space RS1 and a second region A2 corresponding to the second reaction space RS2. The temperature is adjusted differently. That is, the second heating unit 152 sets the temperature of the first region A1 higher than the temperature of the second region A2 so that the first reaction space RS1 and the second reaction space RS2 are set. The temperature between them is formed equally.

Meanwhile, the carbon nanotubes CNT formed in the reaction space RS are discharged to the outside through the recovery line 160. That is, the recovery line 160 is connected to the side wall of the body part 111, and an input terminal through which the carbon nanotubes CNT are sucked is provided in the first reaction space RS1 so that the distribution plate 140 may be formed. Is placed on top. The recovery line 160 receives the metal catalyst in which the carbon nanotubes (CNT) are grown from the reactor 110 and provides an external carbon nanotube collecting device (not shown).

Hereinafter, a process of generating the carbon nanotubes (CNT) in the carbon nanotube manufacturing apparatus 100 will be described in detail with reference to the accompanying drawings.

2 and 3 are views showing a process of manufacturing carbon nanotubes in the carbon nanotube manufacturing apparatus shown in FIG.

Referring to FIG. 2, first, the first and second heating units 151 and 152 heat the reactor 110 to adjust the temperature of the first reaction space RS1 to an appropriate temperature, for example, about 600 degrees Celsius. Rise and hold above.

The catalyst supply nozzle 120 provides the metal catalyst MC to the body part 111, whereby a metal catalyst layer MCL is formed on the upper surface of the dispersion plate 140. Here, since the width of the portion where the dispersion plate 140 is located in the body portion 111 is smaller than in the related art, the thickness of the metal catalyst layer MCL increases. Therefore, the expansion rate of the metal catalyst layer (MCL) is increased, the purity of the carbon nanotubes (CNT) is improved, and the gas utilization rate is improved.

Referring to FIG. 3, the source gas line 130 provides the source gas SG to the body 111. The source gas SG flows into the preheating space PHS through the gas supply hole 111a and flows into the reaction space RS through the distribution holes 141 of the distribution plate 140. . Here, the source gas SG is moved in the order of the dispersion plate 140-> the upper region of the reaction space (RS)-> the side wall of the body portion 111-> the lower region of the reaction space (RS). Circulate.

The metal catalyst MC deposited on the upper surface of the dispersion plate 140 is formed of the first reaction space RS1 and the second reaction space RS2 by the source gas SG passing through the dispersion holes 141. ) And grows the carbon nanotubes (CNT) by reacting with the source gas (SG) while suspended.

In detail, the large particles MCP1 of the metal catalyst MC have a higher velocity of the source gas SG than the second reaction space RS. Is rich in. On the other hand, the small particles MCP2 are suspended in the second reaction space RS2 having a lower speed of the source gas SG than the first reaction space RS1.

As such, the metal catalyst MC is separated according to the size of the particles and suspended by source gas having different speeds, so that the reactor 110 has the small size particles MCP2 open the exhaust port 112a. To prevent it from being discharged. Accordingly, the carbon nanotube manufacturing apparatus 100 may prevent the loss of the metal catalyst MC, improve productivity, and reduce manufacturing cost.

On the other hand, while generating the carbon nanotubes (CNT), the exhaust gas (EG) generated in the reaction space (RS) is sucked into the exhaust device through the exhaust port 112a on the upper surface of the reactor (110). .

When the production of the carbon nanotubes (CNT) is completed, the metal catalyst on which the carbon nanotubes are grown is introduced into the carbon nanotube collecting device through the recovery line 160.

Although described with reference to the embodiments above, those skilled in the art will understand that the present invention can be variously modified and changed without departing from the spirit and scope of the invention as set forth in the claims below. Could be.

1 is a view showing a carbon nanotube manufacturing apparatus according to an embodiment of the present invention.

2 and 3 are views showing a process of manufacturing carbon nanotubes in the carbon nanotube manufacturing apparatus shown in FIG.

Explanation of symbols on the main parts of the drawings

100: carbon nanotube manufacturing apparatus 110: reactor

120: catalyst supply nozzle 130: source gas line

140: dispersion plate 151, 152: heating unit

160: recovery line

Claims (9)

A reactor providing a reaction space in which the metal catalyst and the source gas react with each other to generate carbon nanotubes T); And A dispersion plate provided in the reaction space to disperse the source gas, The reaction space is partitioned into a first reaction space provided with the dispersion plate and a second reaction space located above the first reaction space. The reactor is a carbon nanotube manufacturing apparatus, characterized in that the width corresponding to the first reaction space gradually increases toward the upper side from the dispersion plate. The apparatus of claim 1, wherein a width corresponding to the second reaction space is greater than or equal to a maximum width corresponding to the first reaction space. The apparatus of claim 1, wherein the sidewall of the reactor is inclined at 30 ° to 40 ° with respect to the ground. The apparatus of claim 1, wherein the exhaust port is positioned at an end of the upper surface. The method of claim 1, It is provided adjacent to the outer wall of the reactor, the carbon nanotube manufacturing apparatus further comprises a heating unit for heating the reactor. The apparatus of claim 5, wherein the heating unit has a temperature different from a temperature of the first region corresponding to the first reaction space and the second region corresponding to the second reaction space. The carbon nanotube manufacturing apparatus of claim 6, wherein the heating unit has a temperature of the first region higher than a temperature of the second region. Providing a metal catalyst and a source gas inside the reactor; Increasing the source gas velocity difference between the lower region and the upper region of the reactor to separate the metal catalyst according to the particle size and to float in different regions; And And producing carbon nanotubes by reacting the source gas with the metal catalyst. The method of claim 8, wherein the floating of the metal catalyst, The width of the reactor is increased from the lower end to the upper end so that relatively large metal catalyst particles are suspended in the lower region of the reactor of the source gas, and small metal catalyst particles are suspended in the upper region of the reactor. Carbon nanotube manufacturing method characterized in that.

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