JP2011132078A - Apparatus for manufacturing carbon nanoparticles - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently manufacture carbon nanoparticles while keeping the internal conditions of a cavity-forming section suitable. <P>SOLUTION: After the cavity-forming section 20 is formed at an end of a cathode member 10 and a first graphite part 12 of the cathode member 10 and a second graphite part 42 of an anode member 40 are arranged so as to face each other in the cavity-forming section 20 in an apparatus for manufacturing carbon nanoparticles, an inert gas is supplied through a gas passage 18 to the cavity-forming section 20 soaked in a liquid and an arc is discharged between both the graphite parts to manufacture the carbon nanoparticles. The anode member 40 includes a moving device 46 located outside a reaction vessel 4 and a guide member 44 projecting into the reaction vessel 4, wherein the second graphite part 42 is relatively moved by the moving device 46 vertically along the guide member 44 toward the inside of the cavity-forming section 20. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a production apparatus for producing carbon nanoparticles in a liquid.

As a manufacturing apparatus of this kind of carbon nanoparticles, a manufacturing apparatus of Patent Document 1 is known. This manufacturing apparatus includes a reaction tank (open top) capable of holding a liquid, a cathode member made of bar-shaped graphite, and an anode member made of bar-shaped graphite.
The cathode member has a concave shape at one end (a hollow portion is formed) and has a gas flow path communicating with the hollow portion.

In the known technique, the cathode member is erected vertically with respect to the reaction vessel, and the hollow portion is disposed in the liquid. Then, after the anode member is introduced from the upper part of the reaction tank, the cathode member and the anode member are arranged to face each other by being loosely inserted into a hollow portion in the solution.
Next, while supplying an inert gas from the gas flow path to the hollowed portion, an arc discharge is generated between the cathode member and the anode member to produce carbon nanoparticles. According to this configuration, since the carbon nanoparticles can be manufactured in a hollow portion having a relatively small space, the manufacturing apparatus can be miniaturized or simplified as much as possible.

In the above-described configuration, the carbon nanoparticle can be produced intermittently (in a batch manner) by appropriately replacing the anode member in the liquid.
In the known technique, after the anode member is taken out from the upper part of the reaction tank, a new anode member is loosely inserted into the hollow portion. At this time, after sequentially connecting the anode member manually to a stepping motor or the like, the anode member is again put into the reaction vessel.

By the way, in the manufacturing apparatus described above, the production efficiency of the carbon nanoparticles is lowered, for example, because the same particles adhere to the surface of the cathode member by arc discharge. Therefore, it is necessary to periodically clean the surface of the cathode member.
Therefore, Patent Document 2 discloses a technique in which a cathode member and an anode member can be relatively moved in a horizontal direction in a vacuum. Thus, by moving the anode member in the horizontal direction so as to be separated from the cathode member, the exposed surface of the cathode member can be efficiently cleaned.

JP-A-2005-170739 JP-A-7-216660

By the way, with the technique of patent document 1, it is necessary to fill the inside of a hollow part with an inert gas. At this time, in order to successfully produce carbon nanoparticles (especially single wall carbon nanohorns (SWCNHs)), the inside of the cavitation site as a reaction field needs to be in an inert gas atmosphere of about 760 torr (atmospheric pressure). It is. For this reason, it is necessary to stabilize the atmosphere (internal environment) in the hollowed portion by thoroughly examining various configurations of the cathode member and the anode member (diameter size and gas flow rate of each graphite portion).
However, the technique of Patent Document 2 (the technique of moving the anode member in the horizontal direction) is a technique for producing carbon nanoparticles exclusively in a vacuum, and there is a place where the above consideration is somewhat lacking. For this reason, when the technologies of Patent Documents 1 and 2 are simply combined, there is a risk that defective production of carbon nanoparticles may occur due to gas leakage in the hollowed portion.
Further, when the electrode member is moved in the horizontal direction, the arc plasma may draw an arc and may not be stabilized, and the anode or cathode member may be damaged.
The present invention was devised in view of the above points, and the problem to be solved by the present invention is to efficiently produce or recover carbon nanoparticles while suitably maintaining the internal environment of the hollowed portion. It is in.

As means for solving the above problems, in the carbon nanoparticle production apparatus of the first invention, the cathode member and the anode member are arranged in a sealed reaction vessel capable of holding a liquid. Then, a cavity portion is formed at one end of the cathode member, and the first graphite portion of the cathode member and the second graphite portion of the anode member are disposed facing each other in the cavity portion. Next, the carbon nano particles are produced by generating an arc discharge between the two graphite parts while supplying an inert gas from the gas flow path to the hollow portion in the liquid.
In this type of configuration, it is desirable that the carbon nanoparticles can be efficiently produced by suitably maintaining the internal environment of the hollowed portion.

Therefore, in the present invention, the above-described anode member has a moving member disposed outside the reaction tank and a protruding guide portion inside the reaction tank. And the 2nd graphite part was set as the structure which relatively moves to a perpendicular direction toward a hollow part along a guide part with a moving apparatus.
According to the present invention, the second graphite portion is relatively moved in the vertical direction while disposing the hollow portion at an appropriate position. Thereby, the leakage of the inert gas from the hollowed portion can be prevented or reduced. Furthermore, in this invention, a carbon nanoparticle can be continuously manufactured by supplying a several 2nd graphite part in a hollow part sequentially (continuously).

The carbon nanoparticle production apparatus of the second invention is the production apparatus of the first invention, wherein the first graphite part is separated from the second graphite part by a gas flow of an inert gas or an arc discharge jet flow. Move in the direction (for example, the vertical direction).
In the present invention, an appropriate clearance (arc discharge gap) between the first graphite portion and the second graphite portion can be relatively easily ensured by moving the first graphite portion (by adjusting the arrangement position).

The carbon nanoparticle production apparatus of the third invention is the production apparatus of the first invention or the second invention, wherein the cathode member comprises a rod-shaped first graphite part, a cover part around the first graphite part, It has a removal means.
In the present invention, any one of the cover part and the first graphite part is movable relative to the other different from the other in the vertical direction. And a cover part is arrange | positioned around the 1st graphite part, and a hollow part is formed. Further, the cover portion is relatively moved in the vertical direction so that the first graphite portion is exposed from the cover portion, and then the deposit attached to the first graphite portion is removed by the removing means.
According to the present invention, a hollow portion can be formed with a relatively simple configuration, and the deposit on the first graphite portion can be more reliably removed.

A carbon nanoparticle production apparatus according to a fourth aspect of the present invention is the production apparatus according to any one of the first to third aspects, wherein the cathode member includes a rod-shaped first graphite portion and a periphery of the first graphite portion. And a holding part for holding the first graphite part.
Therefore, in the present invention, a holding part is disposed between the first graphite part and the cover part. And it was set as the structure which forms a gas flow path between a holding | maintenance part and a 1st graphite part, or in a holding | maintenance part. In this way, by forming a gas flow path around the first graphite part and spraying an inert gas on the surface of the first graphite part, the inner surface of the cover part, etc., it is possible to prevent adhesion of deposits to the hollow portion or Can be reduced.

A carbon nanoparticle production apparatus according to a fifth invention is the production apparatus according to any one of the first invention to the fourth invention, wherein at least one of the first recovery device, the second recovery device, and the third recovery device is provided. Have.
The first recovery device can recover the carbon nanoparticles floating in the gas phase in the tank, and the second recovery device can recover the carbon nanoparticles present in the liquid in the tank. The collection device can collect the carbon nanoparticles floating on the liquid surface in the tank.
According to the present invention, the carbon nanoparticles in the tank can be efficiently recovered by at least one of the first recovery device, the second recovery device, and the third recovery device.

  According to the first invention of the present invention, carbon nanoparticles can be efficiently produced while suitably maintaining the internal environment of the hollow portion. According to the second invention, carbon nanoparticles can be produced more efficiently. Moreover, according to the third invention, carbon nanoparticles can be efficiently produced with a relatively simple configuration. According to the fourth invention, carbon nanoparticles can be produced more efficiently. And according to 5th invention, a carbon nanoparticle can be collect | recovered efficiently.

It is the schematic of a manufacturing apparatus. It is a cross-sectional view of a cathode member. It is a longitudinal cross-sectional view of a cathode member, (a) is a figure of the state which raised the cover part, (b) is a figure of the state which lowered | hung the cover part. It is a longitudinal cross-sectional view of the cathode member at the time of washing | cleaning, (a) is a figure before washing | cleaning of a 1st graphite part, (b) is a figure after washing | cleaning of a 1st graphite part, (c) is It is a figure of the state which lowered the cover part after washing. It is a schematic longitudinal cross-sectional view of a cathode member and an anode member. (A)-(g) is a schematic side view of the negative electrode member and positive electrode member which show the relative movement of a 2nd graphite part in order. (A) is a cross-sectional view of a cathode member, (b)-(f) is a cross-sectional view of the cathode member of another example. 6 is a schematic diagram of a manufacturing apparatus of Example 2. FIG. 4 is a schematic longitudinal sectional view of a cathode member and an anode member of Example 2. FIG. It is an observation figure of the carbon nanoparticle using a transmission electron microscope. It is the figure which showed the peak of the carbon nanoparticle by a Raman confusion measurement.

Hereinafter, embodiments for carrying out the present invention will be described with reference to FIGS. In each figure, reference sign UP is given above the manufacturing apparatus, and reference sign DW is given below the manufacturing apparatus.
1 has a reaction vessel 4 capable of holding a liquid, a cathode member 10 (first graphite portion 12), an anode member 40 (second graphite portion 42), and a plurality of recovery devices (each Details of the configuration will be described later). A hollow portion 20 is formed at the lower end of the cathode member 10.

<Embodiment 1>
In this embodiment, the cathode member 10 and the anode member 40 are disposed in the reaction vessel 4 so that the first graphite portion 12 of the cathode member 10 and the second graphite portion 42 of the anode member 40 face each other. Next, while supplying an inert gas from the gas flow path 18 to the hollow portion 20 in the liquid (inhibiting the intrusion of water vapor), an arc discharge is generated between the graphite portions 12 and 42 to generate carbon nanoparticles. To manufacture.
In this type of configuration, it is desirable that the carbon nanoparticles can be efficiently produced or recovered while suitably maintaining the internal environment of the hollow portion 20.
Therefore, in the present embodiment, the carbon nanoparticles are efficiently produced or recovered by the configuration described later. Hereinafter, each configuration will be described in detail.

[Reaction tank]
The reaction tank 4 is a sealed box (substantially rectangular), and includes a plurality of communication portions (4a, 4b, 4c, 4d), a plurality of piping members (6a, 6b), a gas supply device 8, a power supply It has the member E (refer FIG.1 and FIG.5). The shape and dimensions (capacity) of the reaction vessel 4 can be appropriately changed according to the production amount of the carbon nanoparticles. The liquid (kind) is not particularly limited, but is preferably a liquid that is fluid during arc discharge, and typically water can be used.
The reaction tank 4 has a liquid inlet (not shown) and can appropriately replenish the tank with liquid.

The power supply member E is a member that supplies power to the cathode member 10 and the anode member 40 described later, and can be disposed outside the tank.
Moreover, the gas supply apparatus 8 is a member which can supply an inert gas, and can be arrange | positioned outside a tank. The type of the inert gas is not particularly limited, and may be any gas that is less reactive than air, and examples thereof include nitrogen (N ₂ ), helium (He), and argon (Ar).

The first communication part 4 a is a hole communicating with the first pipe 6 a and can be formed in the upper part of the reaction tank 4. The second communication portion 4 b is a hole communicating with a second recovery device 60 described later, and can be formed on one side surface of the reaction tank 4. The third communication portion 4 c is a hole communicating with the second pipe 6 b and can be formed on the other side of the reaction tank 4. The fourth communication portion 4 d is a hole communicating with an anode member 40 described later, and can be formed on the bottom surface of the reaction tank 4.
The first pipe 6a is a pipe having a substantially inverted U shape (side view). One end of the first pipe 6a opens to the upper side of the reaction tank 4 through the first communication part 4a, and the other end of the first pipe 6a communicates with a first recovery device 50 (outside the tank) described later. .
The second pipe 6b is a pipe having a substantially inverted U shape (side view). One end of the second pipe 6b communicates with the third communication portion 4c and opens into the tank, and the other end of the second pipe 6b communicates with the gas supply device 8 outside the tank (outside the tank).

[Cathode member]
The cathode member 10 (rod-like member) includes a first graphite portion 12, a holding portion 14, a cover portion 16, a gas flow path 18, and a removing means 19 (see FIGS. 1 to 5).
In the present embodiment, a hollow portion 20 is formed on one side of the cathode member 10 by the first graphite portion 12, the holding portion 14, and the cover portion 16 described later. The hollow member 20 is disposed on the lower side (in the liquid) while the cathode member 10 is held in the reaction vessel 4. Next, the other side (upper side) of the cathode member 10 is connected to the gas supply device 8 through the second pipe 6b described above.

(First graphite part)
The first graphite portion 12 is a bar-shaped member made exclusively of graphite (see FIGS. 1 to 3). Although the purity of graphite is not particularly limited, for example, graphite having a purity of 99% to 99.999% can be used. The diameter D1 of the first graphite part 12 is not particularly limited, but preferably has a diameter larger than that of the second graphite part 42 (described later).
The first graphite portion 12 of the present embodiment is disposed in the center of the cathode member 10 in a vertically upright state, and is supported by a holding portion 14 described later so as not to move up and down. And the lower end of the 1st graphite part 12 is exposed in the hollowing site | part 20, and can face the below-mentioned 2nd graphite part 42. FIG. A conducting wire L is disposed at the upper end of the first graphite portion 12. The conducting wire L is routed in the second pipe 6b and is electrically connected to the power supply member E outside the reaction tank 4.

(Holding part)
The holding part 14 is a hollow cylindrical member, and includes a gas flow path 18 and a holding mechanism 14a (not shown) (see FIGS. 3 and 4).
In the present embodiment, the first graphite portion 12 is inserted into the holding portion 14. And the upper end of the holding | maintenance part 14 is fixed to the wall surface of the reaction tank 4, the 2nd piping 6b, etc. via the holding mechanism 14a. Thus, the first graphite portion 12 is held at a predetermined position by the holding portion 14 without following the relative movement of the cover portion 16 described later.
Here, an appropriate clearance C1 (arc discharge gap) can be formed between the first graphite portion 12 and the cover portion 16 by appropriately setting the diameter of the holding portion 14 (relatively easily). The dimension of C1 is not particularly limited, but is typically about 2 to 3 mm.

(Gas flow path)
The gas flow path 18 is a flow path for supplying an inert gas to the hollow portion 20 (see FIGS. 2 and 3). The number of gas flow paths 18 can be changed as appropriate depending on the configuration of the hollowed portion 20 (see a modification example described later). For example, when the first graphite portion 12 having a diameter of about 3 mm is used, 2 to 8 gas flow paths 18 can be formed in the holding portion 14.
In the present embodiment, the plurality of gas flow paths 18 are formed on the inner peripheral surface of the holding portion 14 (the surface facing the first graphite portion 12). The plurality of gas flow paths 18 are arranged on the inner peripheral surface of the holding portion 14 at equal intervals (90 °), and each extend in the axial direction of the holding portion 14. The upper end of the gas flow path 18 opens to the upper end of the holding portion 14 and communicates with the second pipe 6b. The lower end of the gas flow path 18 opens to the lower end of the holding portion 14 (in the hollow portion 20).
Then, an inert gas is supplied from the second pipe 6 b to the upper portion of the holding portion 14 and supplied into a cavity 20 described later through the gas flow path 18. Here, the flow rate of the inert gas is not particularly limited, but it is desirable to set the flow rate of the inert gas to be greater than 5 L / min and less than 30 L / min. When the flow rate of the inert gas is 5 L / min or less, arc discharge does not continue stably, and the production amount of carbon nanoparticles tends to be small.

(Cover part)
The cover part 16 is a hollow cylindrical member and has a drive mechanism 16a (not shown) (see FIGS. 2 and 3). Although the thickness dimension D2 of the cover part 16 is not particularly limited, for example, when the first graphite part 12 having a diameter of about 3 mm is used, the thickness dimension D2 of the cover part 16 can be set to 1 to 2 mm.
Moreover, although the structure of the drive mechanism 16a is not specifically limited, a wire member and a cylinder member can be illustrated. For example, after attaching a clamp to the cover part 16, it can be moved up and down by a wire member. Further, the cover portion 16 can be moved up and down by the cylinder member.

In the present embodiment, the holding portion 14 is inserted with respect to the cover portion 16 so as to be relatively movable. And the upper end of the cover part 16 is attached to the wall surface of the reaction tank 4, the 2nd piping 6b, etc. via the drive mechanism 16a which is not shown in figure. As a result, the cover part 16 can be moved relative to the holding part 14 (first graphite part 12) in the vertical direction.
In the present embodiment, the cover portion 16 is relatively moved downward in the vertical direction and arranged around the first graphite portion 12, thereby forming a hollow portion 20 at the lower end of the cathode member 10 (hollow portion 20. Is formed in a suitable position).
By forming the hollow portion 20 at one end of the cathode member 10 in this manner, the gap (arc discharge gap) between the first graphite portion 12 and the second graphite portion 42 is appropriately maintained, and the arc discharge generation region is covered. be able to. In addition, although the protrusion length dimension P1 (depth dimension of a hollow part) of the cover part 16 with respect to the 1st graphite part 12 is not specifically limited, Typically, it is about 5 mm-30 mm (refer FIG. 3).
Further, after the cover part 16 material moves vertically upward to expose the first graphite part 12 from the cover part 16 material, the adhering matter AD attached (deposited) to the first graphite part 12 is removed by a removing means 19 described later. Can be removed.

(Material of holding part and cover part)
Here, the material of the holding portion 14 and the cover portion 16 is not particularly limited, and examples thereof include graphite, metal, and alloy.
The type of metal is not particularly limited, but it is preferable to use a metal that can withstand a high temperature in the vicinity of arc discharge (a stainless alloy such as SUS304, copper, titanium, molybdenum, tungsten, or the like) or an alloy thereof.
In particular, it is preferable to use a metal having a specific gravity different from that of graphite for the material of the holding portion 14 and the cover portion 16. Even if the holding part 14 or the cover part 16 is damaged by the arc discharge, the damaged or crushed material and the carbon nanoparticles precipitate while being separated in water due to the difference in specific gravity, so the purity of the carbon nanoparticles (product) Will not be adversely affected.

(Removal means)
The removing means 19 is a member for removing the deposit AD on the first graphite portion 12 (lower surface), and can be disposed on the lower side of the cathode member 10 (see FIG. 4). Although the shape of the removal means 19 is not specifically limited, A hammer-like removal means and a scraper-like removal means can be exemplified.
The removing means 19 (hammer shape) of the present embodiment includes a substantially rectangular removing portion 32 and a rod-shaped arm portion 34. One end (32 a) of the removing unit 32 has a triangular shape and is fixed to the lower end of the arm unit 34. Then, the upper end of the arm part 34 is attached to the wall surface of the reaction tank 4, and the removal part 32 one end (32 a) is connected to the lower surface (attachment AD) of the first graphite part 12 by sliding movement (horizontal movement) or pendulum movement of the arm part 34. Collide with.
Here, most of the deposits AD are multi-layer carbon nanotubes and large-sized carbon particles, and these tend to be laminated on the lower surface of the first graphite portion 12. Therefore, the deposit AD can be relatively easily separated from the first graphite portion 12 by causing the removal portion 32 to collide horizontally with the deposit AD.

[Anode member]
The anode member 40 (rod-like member) includes a second graphite portion 42, a guide portion 44, a moving member 46, and a supply means 49 (see FIGS. 1, 5, and 6).
The second graphite part 42 is a bar-shaped member made exclusively of graphite. Although the purity of graphite is not particularly limited, for example, graphite having a purity of 99% to 99.999% can be used. The diameter of the second graphite portion 42 is not particularly limited, but can be set to about 2 to 9 mm.

(Guide part)
The guide portion 44 is a rod-like member having a substantially conical tip, and has a holding hole 44h. The holding hole 44 h is a hole that holds the second graphite portion 42 so as to be relatively movable, and can be formed along the axis of the guide portion 44.
Although the material of the guide part 44 is not specifically limited here, It is preferable that it is a material which has electroconductivity, such as a metal. In the present embodiment, a conductive wire L is disposed below the metal guide portion 44 and is electrically connected to the power supply member E outside the reaction vessel 4. As a result, the second graphite portion 42 is electrically connected to the power supply member E via the guide portion 44.

And in this embodiment, the guide part 44 is inserted in the 4th communication part 4d, and is made to protrude toward the inside of the reaction tank 4. FIG. At this time, it is possible to prevent liquid leakage from the fourth communication portion 4d by fitting the O-ring to the fourth communication portion 4d.
Next, the upper portion of the guide portion 44 (holding hole 44 h) in the tank is extended toward the cathode member 10, and the upper opening of the holding hole 44 h is disposed in the hollowed portion 20. And the guide part 44 lower part outside a tank is connected with the below-mentioned moving member 46. FIG. At this time, it is preferable to align the centers (axial centers) of the first graphite portion 12 and the second graphite portion 42 by the guide portion 44. By doing so, an inert gas can be sprayed perpendicularly to the second graphite portion 42, and the second graphite portion 42 can be evenly evaporated by the arc plasma going straight downward.

(Moving member)
The moving member 46 includes a push arm 47 and a drive member 48 that moves the push arm 47 up and down (see FIGS. 1, 5, and 6). The pushing arm 47 is a substantially L-shaped member and has a vertical portion 47a and a horizontal portion 47b.
Although the internal configuration of the drive member 48 is not particularly limited, a stepping motor, a servo motor, an air cylinder, and a combination thereof can be exemplified. Further, the drive member 48 may be a wire rod feeding device (a configuration in which the wire rod is fed in the positive and negative directions).

In the present embodiment, the drive member 48 is disposed adjacent to the guide portion 44 outside the tank while inserting the extrusion arm 47 in the middle of the holding hole 44h (outside the tank) (see FIGS. 5 and 6).
One end of the horizontal portion 47b is inserted into the guide portion 44 so as to be movable up and down, and the other end of the horizontal portion 47b is attached to the drive member 48. For example, the horizontal portion 47b can be inserted into a long hole (not shown) in the middle of the guide portion 44 so as to be movable up and down. And the vertical part 47a is arrange | positioned under the 2nd graphite part 42 in the holding hole 44h. In this state, the vertical portion 47a is moved up and down in the holding hole 44h by moving the horizontal portion 47b up and down by the driving member 48. Thereby, the second graphite portion 42 can be extruded (relatively moved) toward the hollow portion 20 along the guide portion 44 (holding hole 44h).

(Supply means)
The supply means 49 (substantially rectangular member) has the accommodating part 49a and the supply port 49b (refer FIG.5 and FIG.6). The accommodating part 49a is a recessed part in which a plurality of second graphite parts 42 can be arranged in parallel, and the supply port 49b is a hole provided on the position side of the accommodating part 49a.
In the present embodiment, the supply means 49 is disposed in the middle of the guide portion 44, and the supply port 49b communicates with the holding hole 44h. And the 2nd graphite part 42 (for example, 42a-42c) of the accommodating part 49a is horizontally moved toward the supply port 49b in order, and is set as the structure supplied continuously in the holding hole 44h.

[First recovery unit]
The first recovery device 50 is a member that recovers carbon nanoparticles (SWCNHs and the like) suspended in the gas phase in the tank, and includes a first collection unit 52, a first discharge unit 54, and a plurality of pumps P. (See FIG. 1). The 1st discharge part 54 is a member which exhausts gas outside.
The first collection part 52 is a member that captures carbon nanoparticles floating in the gas phase in the tank, and communicates with the first pipe 6 a via the pump P.
In this embodiment, the carbon nanoparticles floating in the gas phase in the tank are sucked out together with the gas in the reaction tank 4 by the pump P. At this time, SWCNHs generally exist as an aggregate having a particle diameter of 70 to 100 nm. And SWCNHs etc. are collected in the 1st collection part 52, and gas is discharged | emitted in the 1st discharge part 54 outside.

Although the 1st collection part 52 (internal structure) is not specifically limited here, A dust collector, a dry classifier, and a solid separation device can be illustrated.
Examples of the dry classifier include an air separator, a cyclone, a ds separator, a turbo classifier, and a micron separator. Further, as the solid separation device, an adsorber using streamer discharge or static electricity can be exemplified.
Moreover, it is preferable that the 1st collection part 52 or the 1st discharge part 54 has film | membrane members, such as a MEPA filter, a HEPA filter, and a ULPA filter. By securing harmful gas and fine particles (for example, SWCNHs having a small particle diameter and light weight) by this film member, external diffusion of the fine particles can be prevented or reduced.

[Second collection device]
The 2nd collection | recovery apparatus 60 is a member which collect | recovers the carbon nanoparticles (SWCNHs etc.) which exist in the liquid (liquid surface or liquid) in a tank (refer FIG. 1). The second recovery device 60 includes a buffer tank 61, a second collection part 62, a slurry tank 63, a second discharge part 64, and a plurality of pumps P.
In the present embodiment, the second collection part 62 is connected to the buffer tank 61, the slurry tank 63, and the second discharge part 64, and the buffer tank 61 is connected to the second communication part 4b. Then, the carbon nanoparticles suspended on the liquid surface or in the liquid are transferred to the buffer tank 61 together with the liquid by the extrusion flow. The second collection unit 62 collects the carbon nanoparticles, and the second discharge unit 64 discharges the liquid to the outside. The collected carbon nanoparticles (typically slurry) are stored (recovered) in the slurry tank 63.

Here, the internal configuration of the second collection unit 62 is not particularly limited, but examples thereof include a centrifugal separator, an ultracentrifugal separator, and a filtration device (a device that uses a filtration membrane or an adsorption membrane). Among these, a filtration device is preferable as a method for separating carbon nanoparticles (solid separation method).
The operation method of the filtration device is not particularly limited, and examples thereof include natural filtration using atmospheric pressure, reduced pressure, pressure filtration, and centrifugal filtration. Examples of the filtration membrane include filter paper, polymer resin, cellulose, glass fiber filter, microfiltration membrane, NF membrane (nanofilter membrane), UF membrane (ultrafiltration membrane), and RO membrane (reverse osmosis membrane). In particular, separation / concentration collection using a UF membrane is suitable for continuous separation / concentration collection of nanocarbon particles.

[Production of carbon nanoparticles]
With reference to FIG.1 and FIG.5, the cathode member 10 and the anode member 40 are arrange | positioned in the reaction tank 4, and the 1st graphite part 12 and the 2nd graphite part 42 face each other. Then, while supplying an inert gas from the gas flow path 18 to the hollow portion 20 in the liquid, an arc discharge is generated between the graphite portions 12 and 42 to produce carbon nanoparticles.
Then, an inert gas is introduced from the periphery of the first graphite portion 12 through the gas flow path 18. At this time, although the adhesion of the adhering material AD to the first graphite portion 12 and the cover portion 16 can be prevented or reduced, the adhering material AD adheres (deposits) in layers on the surface of the first graphite portion 12.

(Recovery work)
Here, the carbon nanoparticles generated by arc discharge are exclusively single wall carbon nanohorns (SWCNHs) and amorphous carbon (amorphous carbon, multiwall carbon nanotubes (MWCNTs, etc.)).
These carbon nanoparticles are separated in the reaction tank 4 according to their specific gravity and the state of the first graphite portion 12 (surface). That is, since SWCNHs is hydrophobic and light, it floats and aggregates on the liquid surface. Also, some SWCNHs blown up vigorously by the inert gas in the hollowed portion 20 cannot be captured at the liquid level and float in the air. Amorphous carbon and the like are heavy and agglomerated so that they are deposited at the bottom of the reaction tank 4.
Therefore, the carbon nanoparticles in the gas phase move to the first collection device 50 and are collected by the first collection unit 52. Further, the carbon nano particles floating on the liquid surface or in the liquid are moved to the second collection device 60 by the extrusion flow in the reaction tank 4 and collected by the second collection unit 62.

(Cleaning work)
After the above arc discharge is completed, the cover portion 16 is raised to expose the first graphite portion 12 (see FIG. 4).
At this time, the deposit AD adhering to the hollow portion 20 (wall surface) is peeled off by the relative movement of the cover portion 16 and the holding portion 14. Here, since the deposit AD hardly adheres to the cover portion 16 (made of metal), the deposit AD can be peeled off relatively easily. Further, a slight amount of adhering material AD is deposited (deposited) on the cover portion 16 (made of graphite), but since it is not chemically bonded to the cover portion 16 (wall surface), the adhering material is relatively smooth in this case as well. AD can be peeled off.
Next, the deposit AD on the surface of the first graphite portion 12 is removed by the removing means 19. At this time, the adhering material AD is not firmly fixed to the first graphite portion 12 and can be removed by the removing means 19 relatively easily. Thus, by removing the deposit AD in the hollow portion 20, the reaction field in the hollow portion 20 can be returned to the initial state.

(Continuous production)
In the present embodiment, the second graphite portion 42 (42a to 42c) is sequentially (continuously) supplied from the lower portion of the reaction tank 4 to the hollow portion 20 through the guide portion 44 (see FIGS. 5 and 6).
At this time, the second graphite portion 42a (first one) in the guide portion 44 rises in the vertical direction until it contacts the second graphite portion 42 at a predetermined control speed by the moving member 46.
Then, arc discharge is started when the second graphite portion 42a contacts the holding portion 14 (touch and start). At this time, the second graphite portion 42a is relatively moved (ascended / descended) or stopped so that the discharge is continued while controlling the setting (a number of parameters such as current and voltage) of the power supply member E.

And the 2nd graphite part 42a (1st) is used to the limit blown off by an arc jet, being extruded by the 2nd graphite part 42b (2nd). At this time, the second graphite portion 42a is raised along the guide portion 44 so that the first graphite portion 12 is accurately faced. Thereby, it can prevent or reduce that the 2nd graphite part 42a contacts the cover part 16 and the holding | maintenance part 14 (contact which disturbs continuous discharge), and can reduce an excess discharge.
And the 2nd graphite part 42b (2nd) is used to the limit blown off by an arc jet, being extruded by the 2nd graphite part 42c (3rd) similarly.

As described above, according to the present embodiment, the plurality of second graphite parts 42 (42a to 42c) are sequentially relatively moved in the vertical direction while the hollow portion 20 is disposed at an appropriate position. Thereby, the leakage of the inert gas from the hollow portion 20 can be prevented or reduced. Moreover, carbon nanoparticle can be continuously manufactured by supplying the 2nd graphite parts 42a-42c in the cavity part 20 sequentially (continuously).
Thus, according to the present embodiment, carbon nanoparticles can be efficiently manufactured by maintaining a suitable internal environment of the hollowed portion 20.

Further, according to the present embodiment, arc discharge can be started again from the start of arc discharge through cleaning (cleaning operation).
For this reason, the inside of the hollow portion 20 (the first graphite portion 12, the holding portion 14, and the cover portion 16) can be maintained in a clean state with little adhesion of the deposit AD. At this time, in the present embodiment, carbon nanoparticles can be continuously produced while controlling the above-described cleaning operation and arc discharge with a member inside or outside the reaction vessel 4.

Furthermore, in this embodiment, since the part to operate | move and the apparatus (moving member 46 etc.) which control operation | movement are arrange | positioned outside a tank (it exists in the environment which does not contact with a liquid), the reaction tank 4 can be sealed. In addition, the first recovery device 50 and the second recovery device 60 can collect the carbon nanoparticles, and can prevent or reduce the external diffusion thereof (there is a preferable exposure prevention effect).
For this reason, according to the apparatus of the present embodiment, it is possible to realize continuous production of carbon nanoparticles as well as prevent exposure by sealing (Ministry of Economy, Trade and Industry “Study Group on Safety Measures for Nanomaterial Manufacturers”). reference).

[Modification]
In this modification, a modification (18b, 18c, 18e) of the gas flow path 18 will be described (see FIG. 7).
For example, in the cathode member 10B, a plurality of gas flow paths 18b can be formed in the first graphite portion 12 (see FIG. 7B). In the cathode member 10C, a plurality of gas flow paths 18c can be formed in the center of the holding portion 14 (see FIG. 7C). In the cathode member 10D, a plurality of gas flow paths 18b and a plurality of gas flow paths 18c can be formed (see FIG. 7D).
Further, in the cathode member 10E, a plurality of serrations (saw-shaped irregularities in a sectional view) are formed on the outer peripheral surface of the first graphite portion 12 (see FIG. 7E). Thereby, a plurality of gas flow paths 18 e can be formed between the first graphite portion 12 and the holding portion 14. In the cathode member 10E, a plurality of gas flow paths 18c and a plurality of gas flow paths 18e can be formed (see FIG. 7 (f)).

<Embodiment 2>
Since the basic structure of the manufacturing apparatus 2A according to the second embodiment is almost the same as that of the first embodiment, a detailed description is omitted by assigning corresponding reference numerals to common structures and the like.
8A includes a reaction vessel 4, a cathode member 10, an anode member 40, a plurality of recovery devices (first recovery device 50, second recovery device 60, and third recovery device 80), and a drying device. 70.
And the manufacturing apparatus of this embodiment is the structure which the cathode member 10 (1st graphite part 12) moves to the direction separated from the 2nd graphite part 42 by the gas flow of an inert gas, or the jet flow of arc discharge ( (See FIG. 9). Hereinafter, each configuration will be described in detail.

[Cathode member]
The cathode member 10 includes a first graphite portion 12, a holding portion 14, a cover portion 16, a gas flow path 18, a removing means 19, and a slide moving mechanism (a column portion 90, a supporting portion 93, an urging portion 94). (See FIG. 8 and FIG. 9).
The column 90 is a member (bar shape) that stands vertically in the tank and has a slide hole 90h. The slide hole 90 h is a hole that extends vertically, and can be formed in the upper part of the support column 90.
Further, the supporting portion 93 is a member (substantially L-shaped) disposed horizontally in the tank and has a slide claw 92. The slide claw 92 is fixed to one end of the carrying portion 93 and can be slidably attached to the slide hole 90h. The second pipe 6 b passes through the support portion 93 and communicates with the cathode member 10.
The urging portion 94 (substantially rectangular) is a member that urges the carrier portion 93 upward, and includes an urging arm 96. The urging portion 94 of the present embodiment can be disposed in the tank. The urging arm 96 is connected to the upper portion of the urging unit 94 via urging means (not shown) (for example, a spring member, a rubber member, a hydraulic cylinder, etc.).

In the present embodiment, the cathode member 10 is attached to the other end (the end extending downward) of the support portion 93. Next, by attaching the slide claw 92 to the slide hole 90h, the support portion 93 is attached to the support column 90 so as to be slidable up and down.
Then, by attaching the urging arm 96 in the middle of the carrying part 93, the carrying part 93 (cathode member 10) is pushed upward by the urging force of the urging part 94. Here, the urging force of the urging unit 94 can be changed as appropriate according to the weight (downward load) of the negative electrode member 10 and the supporting unit 93.

(Production of carbon nanoparticles)
Referring to FIG. 9, the negative electrode member 10 and the positive electrode member 40 are disposed in the reaction vessel 4 so that the first graphite portion 12 and the second graphite portion 42 face each other. Then, while supplying an inert gas from the gas flow path 18 to the hollow portion 20 in the liquid, an arc discharge is generated between the graphite portions 12 and 42 to produce carbon nanoparticles.
At this time, in this embodiment, the cathode member 10 is pushed upward by the gas flow of the inert gas or the jet flow of the arc discharge and the urging force (upward load) of the urging portion 94 (FIGS. 9B and 9C). )). Then, by balancing the upward load and the weight (downward load) of the cathode member 10 and the supporting portion 93, an appropriate clearance between the first graphite portion 12 and the second graphite portion 42 (typically 1 mm to 3 mm) can be ensured (see FIG. 9D).
Then, while maintaining the optimum clearance (arc discharge gap), the second graphite portion 42 is supplied from the lower part of the reaction vessel 4 to the hollow portion 20 through the guide portion 44, whereby the carbon nanoparticles can be efficiently produced. .
As described above, in the present embodiment, an appropriate clearance (arc discharge gap) between the first graphite portion 12 and the second graphite portion 42 is relatively simple by moving the first graphite portion 12 (by adjusting the arrangement position). Can be secured.

[Third recovery device]
The third recovery device 80 is a member that recovers carbon nanoparticles floating on the liquid level in the tank, and includes a roller member 82 (third collection unit), a guide plate 83, and a recovery tank 84. The roller member 82 is a cylindrical member and is rotatable around an axis (see FIG. 8). The material of the roller member 82 is not particularly limited, but is typically made of metal.
In this embodiment, the roller member 82 is attached to the communication hole (not shown) of the buffer tank 61. At this time, the shaft of the roller member 82 is disposed horizontally, and the circumferential surface of the roller member 82 is disposed at a position in contact with the liquid surface of the buffer tank 61. Further, after the guide plate 83 is inclined downward, one side of the guide plate 83 is attached to the communication hole of the buffer tank 61, and the other side of the guide plate 83 is disposed in the collection tank 84 outside the tank.
Then, carbon nanoparticles (SWCNHs or the like) floating in the liquid state of the buffer tank 61 are attached to the peripheral surface of the roller member 82. Next, by rotating the roller member 82, the carbon nanoparticles can be transferred to the collection tank 84 via the guide plate 83.

In the above-described configuration, the airtightness of the reaction tank 4 is ensured by providing a partition plate in the buffer tank 61.
For example, a partition plate (plural or singular) extending from the upper surface of the buffer tank 61 to below the water surface is provided. The carbon nano particles are trapped by the partition plate and the liquid surface so as not to go out together with the gas (N ₂ ). By doing so, the reaction tank 4 can be semi-sealed (sealed) with the water in the buffer tank 61.

[Drying equipment]
The drying device 70 is a member that dries the carbon nanoparticles, and includes a drying unit 72 and a discharge unit 74 (see FIG. 8).
The drying device 70 of this embodiment can be attached to the second recovery device 60 (the upper portion of the slurry tank 63). And in the drying part 72, after drying the carbon nanoparticle (slurry form) collected by the 2nd collection | recovery apparatus 60, the carbon nanoparticle of a dry state is collected. And the gas and liquid which removed the carbon nanoparticle can be discharged | emitted from the discharge part 74 outside.

[Test example]
Hereinafter, although this embodiment is described based on a test example, the present invention is not limited to the test example.
As a present Example, the carbon nanoparticle was manufactured using the manufacturing apparatus of FIG. And the carbon nanoparticle which floats on the liquid level was collect | recovered. The discharge current of the power supply member was set to 50A.
Also with using nitrogen (N ₂₎ as an inert gas, and set its flow rate 25L / min. When the flow rate of nitrogen (N ₂ ) was set to 5 L / min, arc discharge did not continue stably, and the production amount of carbon nanoparticles (product) was small.

In the present example, the diameter of the first graphite part (manufacturer: Toyo Tanso Co., Ltd., product name: ultra-high purity isotropic graphite material IG-110, purity: 99,999%) was set to 9 mm. In addition, the diameter of the second graphite part (Toyo Tanso Co., Ltd., product name: ultra-high purity isotropic graphite material IG-110, purity: 99,999%) is set to φ3 mm and its length is set to 100 mm. did. The clearance (arc discharge gap) between the first graphite part and the second graphite part was set to 2 mm.
In addition, graphite (purity 99,999%, ultra-high purity graphite manufactured by Toyo Tanso Co., Ltd.) was used as the material for the cover part and the holding part. And the thickness dimension of the cover part was set to 1 mm, and the diameter dimension of the holding part was set to 12 mm (that is, the arc discharge gap was set to 3 mm). The projecting length dimension of the cover part relative to the first graphite part (depth dimension of the hollow portion) was set to 15 mm.

(Observation of carbon nanoparticles using a transmission electron microscope)
The obtained carbon nanoparticles (product) were shaken off on a mesh grid of a transmission electron microscope (Transmission Electron Microscope, manufacturer: NEC Corporation, model: JEM-3010) and observed.

(Raman confusion measurement)
The obtained carbon nanoparticles (product) were subjected to spectral analysis of a sample using a laser Raman spectrophotometer (manufacturer: JASCO Corporation, model NRS-21VUV).

[Results and discussion]
In this example, the processing time for one first graphite part (3φ · 100 mm) was about 25 to 30 seconds. The product (carbon nanoparticles) was about 0.4 to 0.5 g per first graphite part.
From this, it was found that in the production apparatus of this example, the yield per unit time (simple calculation) was significantly improved as compared with the technique described in Patent Document 1 (Example 1) (48- 50 g / h · 13-14 times).

Moreover, it was confirmed by TEM observation that the above-mentioned product was a single wall carbon nanohorn (SWCNHs) (see FIG. 10). The particle size of SWCNHs was 20 to 40 nm. In the same observation, impurities (amorphous carbon and multi-wall carbon nanotubes (MWCNTs)) were hardly observed in the product.
Furthermore, a sharp peak was observed in the D-band in the Raman confusion measurement, and it was speculated from the D / G ratio that the product was SWCNHs with few structural defects (see FIG. 11).

From the above test results, it was found that the production apparatus of this example can produce carbon nanoparticles with extremely high purity.
Moreover, according to the manufacturing apparatus of the present Example, it is easily estimated that carbon nanoparticles having extremely high purity can be continuously manufactured by sequentially supplying the second graphite part.

The manufacturing apparatus of the present embodiment is not limited to the above-described embodiment, and can take various other embodiments.
(1) In Embodiment 1, the manufacturing apparatus 2 provided with the 1st collection | recovery apparatus 50 and the 2nd collection | recovery apparatus 60 was illustrated. In the second embodiment, the manufacturing apparatus 2A having the first recovery device 50, the second recovery device 60, and the third recovery device 80 is illustrated.
The structure of these manufacturing apparatuses 2 (2A) can be changed as appropriate. For example, each manufacturing apparatus can have at least one recovery device among a first recovery device, a second recovery device, and a third recovery device. In addition, each manufacturing apparatus can be equipped with no recovery device.
In the present embodiment, the configurations of the first recovery device, the second recovery device, and the third recovery device are illustrated, but the configuration of the recovery devices is not intended to be limited. For example, a 2nd collection | recovery apparatus can be comprised only with a 2nd collection part and a 2nd discharge part.
Further, the manufacturing apparatus 2 (2A) can be equipped with a drying apparatus 70 as necessary. And the drying apparatus 70 can also be provided in the 3rd collection | recovery apparatus 80 (collection tank 84).

(2) In the present embodiment, the configuration in which the cover portion 16 moves has been described. However, the holding portion 14 (the first graphite portion 12) may be moved. At this time, the upper end of the cover part is fixed to the wall surface of the reaction tank or the second pipe via the holding mechanism. Further, the upper end of the holding part (first graphite part) is attached to the wall surface of the reaction tank or the second pipe via a drive mechanism.
(3) Moreover, the power supply member E of this embodiment can be set as the structure which applies a DC voltage to each electrode member, and can also be set as the structure which applies a DC pulse voltage.

(4) In the present embodiment, the example in which the first graphite portion and the second graphite portion are exclusively formed of graphite has been described. However, the configuration of the graphite portions is not intended to be limited.
That is, the first graphite part and the second graphite part may contain a metal (additive) such as iron, nickel, or yttrium. Moreover, an additive can also be provided (spreading, application | coating, plating, or coating) to a part or all of a 1st graphite part and a 2nd graphite part. Further, as the first graphite part and the second graphite part (graphite material), carbon (amorphous carbon, activated carbon, or the like) having a degree of graphitization or purity having conductivity that causes arc discharge can be used.
From the viewpoint of avoiding the modification of the carbon nanoparticles, it is preferable to form the cover part and the holding part with a material different from the additive.
Moreover, in this embodiment, the example which supplies the some 2nd graphite part 42 to the reaction tank 4 sequentially was demonstrated. In contrast to this, a single second graphite part can also be supplied to the reaction vessel (a batch production mode can be adopted).

(5) In the second embodiment, the configuration of the slide movement mechanism (the column portion 90, the support portion 93, and the urging portion 94) is exemplified, but the configuration of the mechanism is not limited. For example, the urging unit can be configured to push up the carrying unit and can be configured to lift the carrying unit.
(6) When the cathode member 10 and the supporting portion 93 are lightweight (when the downward load is small), the supporting portion can be pushed down or pulled downward by the biasing portion. Although the material of a support part is not specifically limited, For example, a metal (relatively heavy material) and resin (relatively light material) can be illustrated.
(7) In the second embodiment, the example in which the cathode member 10 itself is moved in the vertical direction has been described. Unlike this, only the first graphite portion (and the holding portion) can be moved in the vertical direction.
In the second embodiment, the example in which the cathode member 10 is slid and moved has been described. Unlike this, the cathode member 10 (supporting portion 93) may be configured to rotate around the slide claw 92 as a rotation center.
(8) Moreover, in Embodiment 2, although the roller member 82 was illustrated as a 3rd collection part, it is not the meaning which limits the structure of a 3rd collection part. For example, a belt conveyor can be used as the third collection unit. The carbon nanoparticles can be captured by the belt conveyor and transferred to the collection tank as it is (the guide plate can be omitted). A belt conveyor can be used instead of the guide plate.

(9) The purity of the carbon nanoparticles produced by the production method of this embodiment is extremely high. Therefore, the particles can be suitably used for an electron emission source such as a field emission display (FED), a secondary battery material, a gas storage material, and an electromagnetic wave absorber.

2 Manufacturing apparatus 4 Reaction tank 6a First pipe 6b Second pipe 8 Gas supply apparatus 10 Cathode member 12 First graphite section 14 Holding section 16 Cover section 18 Gas flow path 19 Removal means 20 Cavity part 40 Anode member 42 Second graphite Unit 44 guide unit 46 moving member 47 pushing arm 48 drive member 49 supply means 50 first collection device 52 first collection unit 54 first discharge unit 60 second collection unit 61 buffer tank 62 second collection unit 63 slurry tank 64 Second discharge unit 70 Drying device 72 Drying unit 74 Discharge unit 80 Third collection device 82 Roller member 83 Guide plate 84 Collection tank 90 Column 92 Slide claw 93 Supporting unit 94 Energizing unit 96 Energizing arm AD Adhering substance E Power supply member L lead wire

Claims (5)

The cathode member and the anode member are disposed in a sealed reaction vessel capable of holding a liquid, and a hollow portion is formed at one end of the cathode member, so that the first graphite portion of the cathode member and the anode member After disposing the two graphite parts facing each other in the hollowed part, the carbon nanoparticle is generated by generating an arc discharge between the two graphite parts while supplying an inert gas from the gas flow path to the hollowed part in the liquid. In the carbon nanoparticle production apparatus for producing
The anode member has a moving member disposed outside the reaction tank, and a guide portion protruding inside the reaction tank, and the second graphite portion is hollowed along the guide portion by the moving device. A device for producing carbon nanoparticles that moves relative to each other in the vertical direction.   2. The apparatus for producing carbon nanoparticles according to claim 1, wherein the first graphite part moves in a direction away from the second graphite part by a gas flow of the inert gas or a jet flow of the arc discharge. . The cathode member has a rod-shaped first graphite portion, a cover portion around the first graphite portion, and a removing means,
Either one of the cover part and the first graphite part can be moved relative to the other different from the one in the vertical direction,
The cover portion is disposed around the first graphite portion to form the hollow portion, and the cover portion is relatively moved in the vertical direction to expose the first graphite portion from the cover portion. The apparatus for producing carbon nanoparticles according to claim 1 or 2, wherein the deposit attached to the first graphite portion is removed by the removing means. The negative electrode member has a rod-shaped first graphite part, a cover part around the first graphite part, and a holding part for holding the first graphite part,
The configuration is such that the holding portion is disposed between the first graphite portion and the cover portion, and the gas flow path is formed between the holding portion and the first graphite portion or in the holding portion. The manufacturing apparatus of the carbon nanoparticle in any one of 1-3. The manufacturing apparatus has at least one of a first recovery device, a second recovery device, and a third recovery device,
The first recovery device can recover the carbon nanoparticles floating in the gas phase in the tank, the second recovery device can recover the carbon nanoparticles present in the liquid in the tank, The apparatus for producing carbon nanoparticles according to any one of claims 1 to 4, wherein the third recovery device is capable of recovering the carbon nanoparticles floating on the liquid surface in the tank.