JP2010100518A - Method and apparatus for producing carbon nanocoil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for producing a carbon nanocoil, which enable the large-scale synthesis of a carbon nanocoil. <P>SOLUTION: A catalyst carrier, which comprises a particulate carrier and a catalyst comprising a transition metal and supported on the particulate carrier, is filled on a filter which is placed in a cylindrical reactor that extends in the vertical direction. A mixed gas composed of a raw material gas and a carrier gas is supplied through the filter from beneath the filter, while heating the catalyst carrier. In this manner, the catalyst comes in contact with the raw material gas, while fluidizing the catalyst carrier by the action of the mixed gas that is supplied through the filter, whereby a carbon nanocoil is grown on the catalyst. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a carbon nanocoil manufacturing method and manufacturing apparatus, and more particularly, to a carbon nanocoil manufacturing method and manufacturing apparatus that enable efficient synthesis of high-purity carbon nanocoils.

  Since carbon nanocoils are conductive and have a coil shape, they are expected to be used as high-performance electromagnetic wave absorbing materials, and because they are of the order of nanometers, they are materials for micromachine springs and actuators. It is also attracting attention.

  Therefore, in the synthesis process in which carbon nanostructures with various shapes such as linear, curved, and coiled structures are generated, the production rate of carbon nanocoils, which are coiled carbon products, is increased and Research has been conducted to enable mass synthesis for practical use.

  Conventionally, as a method for producing carbon nanocoils, a catalyst film is formed on a substrate, the catalyst is heated in a state of standing in a reaction furnace, and a raw material gas is supplied to generate carbon nanocoils on the substrate. A substrate method (for example, refer to Patent Document 1) and a method for generating carbon nanocoils by spraying powder composed of carbide catalyst fine particles from a spray nozzle into a carbon compound gas have been reported (for example, patents). Reference 2 etc.).

  Among carbon nanostructures, it has been reported that carbon nanotubes are generated in flowing catalyst particles using a fluidized bed method (see, for example, Patent Document 3).

JP 2007-45637 (released February 22, 2007) International Publication No. 2004/105940 Pamphlet (released on December 9, 2004) Special table 2004-526660 (released September 2, 2004)

  However, the conventionally known methods for producing carbon nanocoils are not yet sufficient for efficiently synthesizing high-purity carbon nanocoils.

  In the above substrate method, carbon nanocoils are generated only on the surface of the catalyst formed on the substrate. Therefore, the surface area on which carbon nanocoils can be generated is limited, and it is difficult to perform mass synthesis of carbon nanocoils. is there.

  In addition, since carbon nanocoils have a significantly slower generation rate than carbon nanotubes, it is very difficult to efficiently synthesize carbon nanocoils compared to the synthesis of carbon nanotubes.

  The present invention has been made in view of the above problems, and an object of the present invention is to realize a carbon nanocoil manufacturing method and manufacturing apparatus that can efficiently synthesize high-purity carbon nanocoils. is there.

  In order to solve the above problems, a method for producing a carbon nanocoil according to the present invention includes a catalyst support formed by supporting a catalyst containing a transition metal on a particulate support, and a cylindrical reaction furnace extending in a vertical direction. The catalyst filling step for filling the filter on the installed filter, and the mixed gas containing the raw material gas and the carrier gas is supplied from the lower side of the filter through the filter under the heating of the catalyst carrier, thereby passing the filter through the filter. A carbon nanocoil synthesizing step of growing carbon nanocoils on the catalyst by bringing the catalyst and the raw material gas into contact with each other while flowing the catalyst carrier with a mixed gas.

  According to said structure, there exists an effect that a highly purified carbon nanocoil can be synthesize | combined efficiently.

  In the carbon nanocoil manufacturing method according to the present invention, it is preferable to use, as the reaction furnace, a reaction furnace in which the filter is installed so as to bisect the space in the reaction furnace in the vertical direction.

In the carbon nanocoil manufacturing method according to the present invention, the linear velocity of the mixed gas is preferably controlled to 0.01 m · sec ⁻¹ or more and 50 m · sec ⁻¹ or less.

  Thereby, the said catalyst support body with which the said filter was filled can be made to flow, and there exists the further effect that the synthesis | combination of a carbon nanocoil can be performed favorably.

  In the method for producing carbon nanocoils according to the present invention, a filter installed in the reaction furnace in a state where the catalyst is not filled due to a differential pressure above and below a region filled with the catalyst support in the reaction furnace. It is preferable to fill the catalyst carrier so that the value obtained by subtracting the upper and lower differential pressure is 2 kPa or less after the catalyst is charged and before the heating.

  By filling the catalyst carrier so that the differential pressure is 2 kPa or less, there is an additional effect that the catalyst carrier can be suitably flowed and reacted.

  In the method for producing carbon nanocoils according to the present invention, it is preferable to use a catalyst carrier having an average particle diameter of 10 μm or more and 1 mm or less as the catalyst carrier.

  In the method for producing carbon nanocoils according to the present invention, it is preferable to use a monodispersed catalyst carrier as the catalyst carrier.

  Thereby, since the collision of the particles of the catalyst carrier hardly occurs, there is an additional effect that a longer carbon nanocoil can be synthesized.

In the method for producing carbon nanocoils according to the present invention, the catalyst carrier is filled so that the minimum fluidization speed of the catalyst carrier is less than 0.03 m · sec ⁻¹ after the catalyst filling and before heating. In addition, it is preferable to use a catalyst carrier having a catalyst loading of 0.01% by weight to 0.6% by weight as the catalyst carrier.

When the catalyst carrier is charged in such an amount that the minimum fluidization speed of the catalyst carrier is less than 0.03 m · sec ⁻¹ after the catalyst is charged and before heating, the catalyst having the catalyst loading rate is used. If the support is used, the catalyst support is hardly fixed in the reaction furnace, and the carbon nanocoil can be synthesized more effectively.

In the method for producing carbon nanocoils according to the present invention, the catalyst carrier is filled so that the minimum fluidization speed of the catalyst carrier is 0.03 m · sec ⁻¹ or more after the catalyst is charged and before heating. In addition, it is preferable to use a catalyst carrier having a catalyst loading of 0.01% by weight to 0.3% by weight as the catalyst carrier.

When the catalyst carrier is charged in such an amount that the minimum fluidization speed of the catalyst carrier is 0.03 m · sec ⁻¹ or more after the catalyst is charged and before heating, the catalyst with the catalyst loading rate is used. If the support is used, the catalyst support is hardly fixed in the reaction furnace, and the carbon nanocoil can be synthesized more effectively.

  In the method for producing carbon nanocoils according to the present invention, a reaction furnace provided with a heating device on the outer peripheral portion is used, and a heating region heated by the heating device is used to fill the catalyst carrier packed on the filter. It is preferable to set so as to include a reaction region in which the catalyst and the source gas are brought into contact with each other.

  Thereby, reaction temperature can be controlled suitably by setting a heating area | region according to a reaction area | region. There is a further effect.

  In the method for producing carbon nanocoils according to the present invention, a reaction furnace provided with a heating device on the outer peripheral portion is used, and a heating region heated by the heating device is used to fill the catalyst carrier packed on the filter. It is preferable to set so as to include a reaction region where the catalyst and the source gas are brought into contact with each other and a gas preheating region for heating the carrier gas and / or the source gas before passing through the filter.

  Thereby, by further heating the carrier gas and / or the raw material gas before passing through the filter, it is possible to prevent the temperature of the reaction region from being lowered due to the supplied gas.

  In the method for producing carbon nanocoils according to the present invention, the temperature of the reaction region in which the catalyst carrier packed on the filter is made to flow and the catalyst and the source gas are brought into contact with each other is set to 600 ° C. or higher and 850 ° C. or lower. It is preferable to control.

  By controlling the temperature of the reaction region within the above range, the carbon nanocoil can be preferably produced.

  In the method for producing carbon nanocoils according to the present invention, the temperature of the reaction region in which the catalyst carrier filled on the filter is made to flow and the catalyst and the source gas are brought into contact with each other is 600 ° C. or higher and 850 ° C. In the following, it is preferable to control the temperature of the gas preheating region to 300 ° C. or more and 850 ° C. or less.

  In the method for producing carbon nanocoils according to the present invention, it is preferable to use a catalyst containing at least Fe and Sn as the catalyst.

  By using a catalyst containing at least Fe and Sn, there is an effect that carbon nanocoils with higher purity can be synthesized efficiently.

  In the method for producing carbon nanocoils according to the present invention, it is preferable to use a catalyst having a molar ratio of Fe and Sn of 2 ≦ Fe / Sn ≦ 30 as the catalyst.

  By making the molar ratio of Fe and Sn within such a range, there is an additional effect that a high-purity carbon nanocoil can be produced more efficiently.

  In the method for producing carbon nanocoils according to the present invention, it is preferable to use a catalyst further containing In as the catalyst.

  Thereby, the further effect that a highly purified carbon nanocoil can be manufactured more efficiently is produced.

  In the method for producing carbon nanocoils according to the present invention, as the catalyst, the molar ratio of Fe and Sn is 2 ≦ Fe / Sn ≦ 30, and the molar ratio of In and Sn is 0 ≦ In. It is preferable to use a catalyst with / Sn ≦ 30.

  Thereby, the further effect that a highly purified carbon nanocoil can be manufactured more efficiently is produced.

  In the carbon nanocoil manufacturing method according to the present invention, an oxide is preferably used as the catalyst.

  By using an oxide as the catalyst, the catalyst does not oxidize any more even when used in the air and is chemically stable, so that the carbon nanocoil can be synthesized stably. .

  In order to solve the above problems, the carbon nanocoil manufacturing apparatus according to the present invention is a cylindrical reaction furnace having a filter installed therein and extending in the vertical direction, and the catalyst carrier is packed on the filter. A reaction furnace having a reaction zone, a heating device installed at least on the outer periphery of the reaction zone, and a raw material gas and / or a carrier gas from below the filter of the reaction furnace is supplied through the filter And a gas introduction part.

  According to said structure, there exists an effect that a highly purified carbon nanocoil can be synthesize | combined efficiently.

  In the method for producing carbon nanocoils according to the present invention, as described above, a catalyst carrier formed by supporting a catalyst containing a transition metal on a particulate carrier is installed in a cylindrical reaction furnace extending in the vertical direction. A catalyst filling step of filling the filter and a mixed gas containing a raw material gas and a carrier gas from the lower side of the filter under the heating of the catalyst carrier to supply the mixed gas through the filter with the mixed gas. Since it comprises a structure characterized by including a carbon nanocoil synthesizing step of growing carbon nanocoils on the catalyst by bringing the catalyst and the raw material gas into contact with each other while flowing the catalyst carrier, The effect is that high-purity carbon nanocoils can be synthesized efficiently.

It is a figure which shows typically the manufacturing apparatus of the carbon nano coil concerning this invention. In an Example, it is a figure which shows the result of having observed the carbon nano coil produced | generated on the catalyst with the scanning electron microscope. In an Example, it is a figure which shows the result of having observed the carbon nano coil produced | generated on the catalyst with the scanning electron microscope. It is a graph which shows the relationship between the linear velocity of mixed gas in an Example, and the differential pressure | voltage in the upper and lower sides of a catalyst support body. It is a graph which shows the relationship between the linear velocity of mixed gas in an Example, and the differential pressure | voltage in the upper and lower sides of a catalyst support body. In an Example, it is a figure which shows the result of having observed the production | generation of the carbon nano coil when the composition of a catalyst was changed with the scanning electron microscope. In an Example, it is a figure which shows the result of having observed the production | generation of the carbon nano coil when the composition of a catalyst was changed with the scanning electron microscope. In an Example, it is a figure which shows the particle size distribution of the used catalyst support body, and the result of having observed the produced | generated carbon nano coil with the scanning electron microscope. In an Example, it is a figure which shows the particle size distribution of the used catalyst support body, and the result of having observed the produced | generated carbon nano coil with the scanning electron microscope. In an Example, it is a figure which shows the result of having observed the production | generation of the carbon nanocoil when changing the catalyst supporting rate with the scanning electron microscope. In an Example, it is a figure which shows the result of having observed the production | generation of the carbon nanocoil when changing the catalyst supporting rate with the scanning electron microscope.

  An embodiment of the present invention will be described below with reference to FIGS.

(I) Method for Producing Carbon Nanocoil The method for producing carbon nanocoil according to the present invention is a cylindrical reaction furnace in which a catalyst carrier formed by carrying a catalyst containing a transition metal on a particulate carrier is extended in the vertical direction. A catalyst filling step of filling the filter installed on the filter, and supplying the mixed gas containing the raw material gas and the carrier gas from below the filter through the filter under heating of the catalyst carrier, through the filter A carbon nanocoil synthesizing step of growing carbon nanocoils on the catalyst by bringing the catalyst and the raw material gas into contact with each other while flowing the catalyst carrier with the mixed gas.

  In addition, the method for producing carbon nanocoils according to the present invention may further include a catalyst carrier preparation step for preparing the catalyst carrier, and may further include other steps. Below, the manufacturing method of the carbon nanocoil concerning this invention is made into (I-1) catalyst filling process, (I-2) carbon nanocoil synthesis | combination process, (I-3) catalyst carrier preparation process, (I-4) ) The other steps will be described in this order.

(I-1) Catalyst filling step In this step, a catalyst carrier formed by carrying a catalyst containing a transition metal on a particulate carrier is filled on a filter installed in a cylindrical reaction furnace extending in the vertical direction. To do.

<Filter installed in the reactor>
The reaction furnace used in the present invention is provided with a filter so that the catalyst carrier can be filled thereon. In the present invention, the filter may be any filter that does not substantially pass the catalyst carrier, but can pass the carrier gas and the raw material gas.

  Such a filter is installed in a reaction furnace so that the catalyst carrier can be filled thereon, and a raw material gas and a carrier gas can be supplied from below the filter to the catalyst carrier through the filter. Just do it. With this configuration, the catalyst and the raw material gas can be brought into contact with each other while the catalyst carrier filled on the filter is caused to flow with the mixed gas passing through the filter.

  Here, as the reaction furnace, it is more preferable to use a cylindrical reaction furnace extending in the vertical direction, and the filter is configured so that the raw material gas and the carrier gas pass through only the filter from the lower side of the filter and carry the catalyst. More preferably, it is installed so as to be supplied to the body.

  As a preferred example, for example, as schematically shown in FIG. 1, a cylindrical reaction furnace extending in the vertical direction is used as the reaction furnace, and the filter bisects the space in the reaction furnace in the vertical direction. The structure installed in can be used suitably. With such a configuration, the catalyst carrier can be flowed on the filter, so that the carbon nanocoil can be efficiently manufactured by flowing in a region where the heat necessary for the reaction is continuously supplied. Further, since the source gas and the carrier gas are supplied to the catalyst carrier on the filter through the filter, the linear velocity of the source gas and the carrier gas can be suitably controlled. Furthermore, it is preferable that the surface of the filter is installed perpendicular to the vertical direction of a cylindrical reactor extending in the vertical direction. Thereby, the catalyst carrier can be uniformly filled on the filter. Therefore, the catalyst carrier can be efficiently brought into contact with the raw material gas, and carbon nanocoils can be efficiently produced.

  Further, the filter is stably fixed to the reactor in the step of bringing the catalyst and the source gas into contact with each other while supplying the mixed gas containing the source gas and the carrier gas from the lower side of the filter through the filter. If so, the method of installation is not particularly limited. As such an installation method, the filter may be directly welded to the reaction furnace, may be fixed with a screw or the like, or may be fixed by a method of fitting into a groove installed in the reaction tube and pressing from the top. It is more preferable that the space between the sides of the reaction furnace is sealed so that the raw material gas and the carrier gas do not pass from other than the filter portion.

The material of the filter is not particularly limited as long as the filter does not adversely affect the synthesis of the carbon nanocoil. For example, a filter made of quartz; metal; ceramics such as A1 ₂ 0 ₃ can be preferably used.

  Further, the pore diameter of the filter may be smaller than the particle diameter of the catalyst support and may be in a range that does not substantially pass the catalyst support. Specifically, the pore diameter of the filter is preferably 10 μm or more and 500 μm or less, and more preferably 40 μm or more and 100 μm or less. When the pore diameter of the filter is within the above range, the catalyst carrier is not substantially passed, but the carrier gas and the raw material gas can be passed.

<Catalyst carrier>
In this step, a catalyst carrier formed by carrying a catalyst containing a transition metal on a particulate carrier is filled on the filter.

  By using such a catalyst carrier, the surface area capable of generating carbon nanocoils can be increased as compared with the substrate method in which carbon nanocoils are generated only on the catalyst surface formed on the substrate. Therefore, carbon nanocoils can be synthesized efficiently. Moreover, since the particulate carrier has a heat storage function compared to the case where the catalyst particles not supported on the carrier are used as they are, it is possible to prevent the temperature of the catalyst from being lowered. Therefore, the temperature condition of the reaction can be stabilized, and carbon nanocoils can be synthesized efficiently.

  As the catalyst used in the present invention, a catalyst containing a transition metal can be suitably used. By using such a catalyst, high-purity carbon nanocoils can be produced.

  Here, the transition metal is not particularly limited as long as it is a transition metal, but for example, Fe, Co, Ni, Mo, Cu, and the like are more preferable. Although the said catalyst should just be a catalyst containing a transition metal, it should just contain 1 or more types of transition metals. Moreover, as long as it contains one or more transition metals, it may further contain elements other than the transition metals. As the catalyst, for example, a Fe—Sn catalyst, a Fe—Sn—In catalyst, a Co—Mo catalyst, a Ni—S catalyst, a Ni—Cu catalyst, a SUS catalyst, Co, Ni, or the like is preferably used. be able to. Although the said catalyst should just contain the said transition metal and said element, the said transition metal and said element may be contained as various compounds, such as an oxide, a carbonyl derivative, an organic compound, and a metal salt.

  Especially, as a catalyst used by this invention, the catalyst which contains Fe and Sn at least can be used more suitably. Higher purity carbon nanocoils can be produced by using such a catalyst.

  Here, the ratio of the catalyst containing at least Fe and Sn is not particularly limited as long as it contains Fe and Sn, but the molar ratio of Fe to Sn is 2 ≦ Fe / Sn ≦ 30. Preferably, 3 ≦ Fe / Sn ≦ 10, more preferably 5 ≦ Fe / Sn ≦ 10. By setting the molar ratio of Fe and Sn within such a range, high-purity carbon nanocoils can be produced more efficiently.

  In the present invention, a catalyst containing In in addition to Fe and Sn can also be suitably used. Even when In is contained, the molar ratio of Fe and Sn is preferably within the above range, and the molar ratio of In and Sn is preferably 0 ≦ In / Sn ≦ 30, and 1 ≦ In / Sn ≦ 10 is more preferable, and 1.2 ≦ In / Sn ≦ 4 is even more preferable. By setting the molar ratio of Fe, Sn, and In within such a range, high-purity carbon nanocoils can be more efficiently produced.

  In addition, from the viewpoint that a high-purity carbon nanocoil can be more efficiently produced, the catalyst has (i) Fe: In molar ratio of 3: 1 and Sn is 10% or more of Fe. A catalyst having a molar ratio of 33% or less, or (ii) a catalyst having a molar ratio of Fe: Sn of 7.5: 1 and In having a molar ratio of 33% to 66% of Fe. It can be used suitably.

  The catalyst used in the present invention is particularly preferably an Fe—Sn catalyst, that is, a two-component catalyst containing Fe and Sn, or an Fe—Sn—In catalyst, ie, Fe, Sn, and In. A three-component catalyst. However, the catalyst may contain other metals in addition to Fe and Sn, or Fe, Sn, and In as long as they do not adversely affect the synthesis of the carbon nanocoil. Examples of other metals include Al and Na.

Although the said catalyst should just contain the said metal element, the said metal element may be contained as various metal compounds. For example, Fe is an iron oxide such as Fe ₂ O ₃ and Fe ₃ O ₄ ; an iron organic compound such as iron carboxylate, iron carbonyl, iron carbonyl derivative, iron nitrosyl, iron nitrosyl derivative; iron nitrate, iron chloride, sulfuric acid It can be included in the catalyst as a metal salt such as iron. In is, for example, indium oxide such as In ₂ O ₃ ; indium organic compounds such as trimethylindium, triphenylindium, indium octylate, and indium carboxylate; metal salts such as indium nitrate, indium chloride, and indium sulfate. As included in the catalyst. In addition, Sn is used as a catalyst as a tin oxide such as SnO or SnO ₂ ; a tin organic compound such as triethyltin, tetraphenyltin, tin octylate or tin carboxylate; a metal salt such as tin chloride or tin sulfate. May be included. Above all, the use of oxides does not oxidize any more even when the catalyst is used in the air and is chemically stable, so that the carbon nanocoil can be synthesized stably. It is more preferable that it is contained.

  The particulate carrier carrying the catalyst is not particularly limited as long as it can carry the catalyst and does not react with the raw material gas. For example, alumina, ceramics, zeolite, etc. Particles such as aluminophosphate, silica aluminophosphate, resin, magnesia, ceria, silica, zirconia can be suitably used. Among these, from the viewpoint of being stable even during the CVD reaction, the particulate carrier is more preferably a ceramic such as alumina, silica, or zeolite.

  The shape of the particulate carrier and the catalyst carrier is not particularly limited as long as it is particulate, and examples thereof include a spherical shape, a substantially spherical shape, a rod shape, and a cubic shape. Among these, from the viewpoint of creating a stable fluid state, the shape of the particulate carrier is more preferably spherical.

  The average particle diameter of the particulate carrier and the catalyst carrier is preferably 10 μm or more and 1 mm or less, more preferably 20 μm or more and 500 μm or less, and further preferably 40 μm or more and 150 μm or less. If the average particle diameter of the particulate carrier is 10 μm or more, it is preferable because the carrier can stay in the furnace for a long time within the range of the gas linear velocity used. Moreover, it is preferable if the average particle diameter of the particulate carrier is 1 mm or less because a stable fluid state can be maintained and a surface area for growing carbon nanocoils can be sufficiently secured.

  In addition, in this specification, an average particle diameter means the value determined with the following method. The particulate carrier and the catalyst carrier are observed with a scanning electron microscope, and for each particle in the obtained observation image, the major axis diameter of one particle, that is, the direction of the largest dimension of the particle shape Are measured from a micrograph. A value obtained by averaging the measured values is defined as an average particle diameter in the present invention.

  Further, it is more preferable to use the monodispersed particulate carrier and catalyst carrier as the particulate carrier and catalyst carrier. Here, “monodispersed” is not particularly limited as long as the particle size of the catalyst carrier is uniform, but the particle size distribution is narrow and the relative standard deviation of the particle size is 70% or less. Is preferable, and it is more preferable that it is 20% or less. The relative standard deviation of the particle diameter is a value that expresses the standard deviation of the particle diameter as a percentage based on the average value of the population of observed values.

  By using a monodispersed catalyst carrier, collisions between particles of the catalyst carrier are less likely to occur than when a catalyst carrier having a large particle size distribution is used. Therefore, longer carbon nanocoils can be synthesized. In addition, when using a monodispersed catalyst carrier, the amount of catalyst carrier with a small particle size that moves out of the heating region through a filter or is scattered by the mixed gas and released outside the heating region is small. Therefore, the yield of carbon nanocoil synthesis can be improved.

  Further, the catalyst loading rate of the catalyst carrier is preferably in the range of 0.01 wt% to 0.6 wt%. Here, the catalyst support rate of the catalyst support refers to the ratio of the weight of the catalyst to the weight of the entire catalyst support, and is a value represented by the following formula. Here, the weight of the catalyst is determined from the difference between the weight of the particulate carrier before loading the catalyst and the weight of the catalyst carrier obtained by loading the catalyst on the particulate carrier.

Catalyst loading ratio (% by weight) = (weight of catalyst / weight of entire catalyst carrier) × 100
The catalyst is not particularly limited as long as it is supported on a particulate carrier. The method for supporting the catalyst on the particulate carrier is not particularly limited, and for example, it can be supported by a liquid phase method, a gas phase method, a solid phase method or the like, which will be described later.

<Filling of catalyst carrier>
In this step, the method for filling the catalyst carrier onto the filter is not particularly limited, and any method may be used. For example, what is necessary is just to introduce | transduce from catalyst introduction parts, such as a catalyst introduction pipe and a catalyst inlet provided in the reaction furnace.

  Here, the amount of the catalyst carrier to be filled needs to be an amount capable of flowing the catalyst carrier with the mixed gas passing through the filter. In the present invention, the catalyst carrier flows when the catalyst carrier is filled and is convected by being pushed up into the air by a gas flow, but is convected near the upper end of the packed catalyst carrier. The state that doesn't scatter. As a method for controlling the amount of the catalyst carrier to be filled so that the catalyst carrier can be flowed, the present inventors have determined the pressure difference before and after passing through the catalyst carrier filled with the gas flow, that is, Attention was paid to the pressure difference between the upper and lower areas of the catalyst carrier in the reactor. More specifically, the differential pressure above and below the filter installed in the reaction furnace in a state where the catalyst is not filled from the differential pressure above and below the area where the catalyst carrier is filled in the reaction furnace. Pay attention to the subtracted value. Then, a value obtained by subtracting the differential pressure above and below the filter installed in the reaction furnace in a state where the catalyst is not filled from the differential pressure above and below the area filled with the catalyst carrier in the reaction furnace. It has been found that the catalyst carrier can be suitably flowed by filling the catalyst carrier so as to be 2 kPa or less after heating and before heating. “After charging the catalyst and before heating” may be any temperature before heating the catalyst carrier, but is usually at room temperature, for example, at a temperature of −5 ° C. to 40 ° C. Hereinafter, even when simply referred to as “differential pressure” in the present specification, it means a differential pressure after filling the catalyst and before heating.

  The differential pressure above and below the region filled with the catalyst carrier in the reactor is, in other words, the region between the gas introduction part and the filter, and the upper end of the region filled with the catalyst carrier. It is a differential pressure | voltage with the area | region between the gas exhaust parts which exhaust gas from a reaction furnace. It can also be said that the pressure difference is between the gas introduction part and the gas exhaust part.

  Therefore, a value obtained by subtracting the differential pressure above and below the filter installed in the reactor in a state where the catalyst is not filled from the differential pressure above and below the region in the reactor where the catalyst carrier is filled. In other words, from the differential pressure between the gas introduction part and the gas exhaust part in the state filled with the catalyst, the gas introduction part and the gas exhaust part in the state not filled with the catalyst It is the value which subtracted the pressure difference between.

  Here, the differential pressure can be measured, for example, using the method shown in the examples described later.

  The value obtained by subtracting the differential pressure above and below the filter installed in the reactor in a state where the catalyst is not filled from the differential pressure above and below the region filled with the catalyst carrier in the reactor is the catalyst Although it is preferably 2 kPa or less after filling and before heating, it is more preferably 0.2 kPa or more and 1 kPa or less, and further preferably 0.3 kPa or more and 0.7 kPa or less.

  Therefore, for example, in this step of filling the catalyst carrier onto the filter, the catalyst pressure is measured by supplying the carrier gas from below the filter and filling according to the measurement result of the differential pressure. A method of filling the catalyst carrier onto the filter while controlling the amount of the body can be suitably used.

  In addition, the method of filling the catalyst carrier onto the filter while controlling the amount of the catalyst carrier may be performed manually, but a storage container storing the catalyst carrier to be introduced is connected to the reaction furnace. The catalyst carrier may be filled on the filter while automatically controlling the amount of the catalyst carrier to be filled according to the measured value of the differential pressure gauge.

The value obtained by subtracting the differential pressure above and below the filter installed in the reactor in a state where the catalyst is not filled from the differential pressure above and below the region filled with the catalyst carrier in the reactor is the catalyst. The catalyst carrier is preferably filled so as to be 2 kPa or less after filling and before heating, but the catalyst carrier having a predetermined catalyst loading rate according to the minimum fluidization speed of the catalyst carrier. More preferably, is used. For example, when the catalyst carrier is filled so that the minimum fluidization speed after heating and before heating is less than 0.03 m · sec ⁻¹ , the catalyst carrier is 0.01% as the catalyst carrier. It is particularly preferable to use a catalyst carrier having a weight% of 0.6% or less. When filling the catalyst carrier so that the minimum fluidization speed of the catalyst carrier is less than 0.03 m · sec ⁻¹ , if a catalyst carrier having the catalyst loading rate is used, the carbon nanocoil synthesis step The catalyst carrier is hardly fixed in the reaction furnace, and the carbon nanocoil can be synthesized more satisfactorily.

  Here, the minimum fluidization speed refers to the minimum gas linear velocity in the reaction region where the catalyst carrier filled in the reaction furnace starts to flow, and is determined using the method shown in the examples described later.

Further, for example, when the catalyst carrier is filled so that the minimum fluidization speed of the catalyst carrier after heating and before heating becomes 0.03 m · sec ⁻¹ or more, a catalyst is used as the catalyst carrier. It is particularly preferable to use a catalyst carrier having a loading rate of 0.01% by weight to 0.3% by weight. When the catalyst carrier is filled so that the minimum fluidization speed of the catalyst carrier is 0.03 m · sec ⁻¹ or more, the catalyst carrier in the reaction furnace can be obtained by using the catalyst carrier having the catalyst loading rate. It is difficult for the body to stick, and carbon nanocoils can be synthesized better.

(I-2) Carbon nanocoil synthesis step In this step, under the heating of the catalyst carrier, the mixed gas containing the raw material gas and the carrier gas is supplied from below the filter through the filter to pass the filter. While the catalyst carrier is fluidized with a mixed gas, the catalyst and the source gas are brought into contact with each other to grow carbon nanocoils on the catalyst.

<Heating of catalyst carrier>
In this step, carbon nanocoils are synthesized while heating the catalyst carrier. The catalyst carrier may be heated when the catalyst and the source gas are brought into contact with each other, but it is more preferable that the catalyst carrier is heated in advance before the supply of the source gas. Thereby, the synthesis | combination of a carbon nanocoil can be performed on suitable temperature conditions from the beginning. Therefore, carbon nanocoils can be synthesized efficiently.

  From the viewpoint of preventing reaction with the raw material gas, it is more preferable to remove oxygen in the reaction furnace before heating the catalyst carrier.

  Here, the method of heating the catalyst carrier is not particularly limited. For example, a method of heating the catalyst carrier by the heating device using a reaction furnace provided with a heating device on the outer periphery. Can be mentioned. Of course, heating by a heating device provided inside the reaction furnace is also possible, but it is more preferable to install a heating device on the outer periphery of the reaction furnace in terms of the device structure and maintenance. Also, the heating device is not particularly limited, and for example, a resistance heating furnace, an infrared heating furnace, or the like can be suitably used.

  The region of the reaction furnace that is heated to heat the catalyst carrier includes a reaction region in which the catalyst carrier filled on the filter is caused to flow and the catalyst and the source gas are brought into contact with each other. It is preferable that In order to heat such a region, for example, a reaction furnace provided with a heating device on the outer peripheral portion is used, and the heating region heated by the heating device flows the catalyst carrier packed on the filter. And a reaction region where the catalyst and the source gas are brought into contact with each other may be included. In the present invention, the catalyst carrier is filled on the filter and the catalyst carrier is caused to flow on the filter, so that the reaction region can be easily defined. Therefore, the reaction temperature can be suitably controlled by setting the heating region in accordance with the reaction region. In addition, by allowing the catalyst carrier to flow in the reaction region for a long time and maintaining the heat capacity, it is possible to synthesize a large amount of carbon nanocoils by effectively using the space in the reaction furnace.

  Further, in this step, in addition to the region including the reaction region where the catalyst carrier filled on the filter is fluidized to contact the catalyst and the source gas, the carrier gas before passing through the filter and It is more preferable that the gas preheating region for heating the raw material gas is a heating region. In order to heat such a region, for example, a reaction furnace provided with a heating device on the outer peripheral portion is used, and the heating region heated by the heating device flows the catalyst carrier packed on the filter. Thus, a reaction region where the catalyst and the source gas are brought into contact with each other and a gas preheating region for heating the carrier gas and / or the source gas before passing through the filter may be included. By preheating the carrier gas and / or the raw material gas before passing through the filter, it is possible to prevent a temperature drop in the reaction region due to the supplied gas. Therefore, the reaction temperature can be controlled to be constant, and carbon nanocoils can be synthesized efficiently.

  In the above description, an example using a reaction furnace provided with a heating device at the outer peripheral portion is described. However, instead of a heating device provided at the outer peripheral portion, a heating device provided inside the reaction furnace is used. You can use it.

  In this step, the temperature of the reaction region is preferably 600 ° C. or higher and 850 ° C. or lower, and the temperature of the gas preheating region is preferably controlled at 300 ° C. or higher and 850 ° C. or lower. By controlling the temperature of the reaction zone and the temperature of the gas preheating zone within the above ranges, it is possible to suppress the decomposition and polymerization of the raw material gas in the preheating zone and promote the reaction of the catalyst and the raw material gas in the reaction zone. Therefore, the carbon nanocoil can be suitably manufactured.

<Supply of mixed gas>
In this step, the mixed gas containing the raw material gas and the carrier gas is supplied from below the filter through the filter. Thereby, the catalyst carrier can be flowed by the mixed gas passing through the filter, and the catalyst flowing on the filter and the raw material gas can be brought into contact with each other to grow carbon nanocoils on the catalyst. .

  The method of supplying the mixed gas from the lower side of the filter through the filter is not particularly limited. For example, a gas introduction part such as a gas introduction port and a gas introduction pipe is provided at the bottom of the reaction furnace to introduce the gas. A mixed gas containing the source gas and the carrier gas may be introduced from the section. In order to optimize the flow, it is also effective to use an appropriate mixed gas supply nozzle for the gas introduction part at the lower part of the filter.

  The source gas is not particularly limited as long as it is a molecule that becomes a carbon source. For example, hydrocarbons such as acetylene, ethylene, methane, hexane, and benzene; alcohols such as methanol and ethanol are used. It is done.

  The carrier gas is not particularly limited as long as it is an inert gas. For example, helium, nitrogen, argon, or the like can be suitably used.

  Further, the amount of the raw material gas contained in the mixed gas is preferably 2% by volume or more and 50% by volume or less, more preferably 3% by volume or more and 30% by volume or less, more preferably 5% by volume with respect to the mixed gas. % To 20% by volume is more preferable. When the amount of the raw material gas is 2% by volume or more with respect to the mixed gas, the carbon nanocoil can be synthesized well. Further, it is preferable that the amount of the raw material gas is 50% by volume or less with respect to the mixed gas, because waste of the raw material gas due to tar generation or the like can be suppressed.

Here, the linear velocity of the mixed gas is preferably controlled to 0.01 m · sec ⁻¹ or more and 50 m · sec ⁻¹ or less, and controlled to 0.02 m · sec ⁻¹ or more and 50 m · sec ⁻¹ or less. Is more preferable, and it is further more preferable to control to 0.04 m · sec ⁻¹ or more and 50 m · sec ⁻¹ or less. The linear velocity refers to the speed at which gas passes through the reactor in unit time, and the flow rate refers to the volume of gas flowing in unit time.

When the linear velocity of the mixed gas is 0.01 m · sec ⁻¹ or more, the catalyst carrier filled on the filter can be flowed, and the carbon nanocoil can be synthesized well. it can. Moreover, when the linear velocity of the mixed gas is 50 m · sec ⁻¹ or less, the catalyst carrier filled on the filter can be flowed well.

  In this step, the catalyst carrier can be fluidized with the mixed gas passing through the filter by supplying the mixed gas containing the raw material gas and the carrier gas from below the filter through the filter.

<Growth of carbon nanocoils>
In this step, carbon nanocoils are grown on the catalyst by bringing the catalyst and the raw material gas into contact with each other while flowing the catalyst carrier filled on the filter as described above.

  Here, the carbon nanocoil is a carbon coil in which carbon atoms are wound and grown in a spiral shape, and the coil diameter may be any as long as the coil diameter is 1000 nm or less. Therefore, the carbon atoms that spirally grow and grow may be carbon nanotubes having a hollow interior, solid carbon fibers in the interior, or a mixture thereof.

  The carbon nanostructures grown on the catalyst may contain a small amount of carbon nanostructures that are not spirally grown in addition to the carbon nanocoils. The ratio of the carbon nanocoil to the nanostructure, that is, the purity of the carbon nanocoil is preferably 70% or more, more preferably 80% or more, and further preferably 90% or more.

(I-3) Catalyst carrier preparation step In the catalyst carrier preparation step, the catalyst is supported on the particulate carrier. The method for supporting the catalyst on the particulate carrier is not particularly limited as long as the above-described catalyst support can be obtained, and a conventionally known method can be suitably used. As such a method, a liquid phase method, a gas phase method, a solid phase method, or the like can be used.

  Hereinafter, the case where the liquid phase method is used will be described as an example, but the method for preparing the catalyst carrier used in this step is not limited thereto.

<Preparation of catalyst solution>
The transition metal and other element compounds used as the catalyst are dissolved in a solvent to obtain a catalyst solution. Although it does not specifically limit as this compound, Inorganic compounds, such as the organic compound quoted by said (I-1); chloride, nitrate, sulfate, carbonate, can be used. Moreover, what is necessary is just to select suitably the solvent which can melt | dissolve the said compound as said solvent. Such a solvent is not particularly limited and may be appropriately selected depending on the compound to be used. Examples of such a solvent include alcohol and water.

<Supporting on particulate carrier>
A catalyst solution obtained by immersing the particulate carrier in the catalyst solution, a method of applying the catalyst solution to the particulate carrier by a known method, or the like is attached to the particulate carrier. In the method of immersing the particulate carrier in the catalyst solution, the solution may be agitated or sonicated in order to adhere the catalyst solution more efficiently.

  The particulate carrier to which the catalyst solution is adhered is dried and calcined to obtain a catalyst carrier containing a desired catalyst. Here, although a calcination temperature is not specifically limited, Usually, it is 400 to 1200 degreeC. The firing time is usually 0.5 hours to 48 hours. By firing in an oxidizing atmosphere, the metal compound changes to a metal oxide.

(I-4) Other steps The carbon nanocoil manufacturing method according to the present invention may further include, as other steps, a carbon nanocoil recovery step for recovering the generated carbon nanocoils, an apparatus cleaning step, and the like. Good.

  The method for recovering the generated carbon nanocoil is not particularly limited, and a conventionally known method can be suitably used. For example, after cooling the reaction furnace to room temperature, the catalyst carrier in which the carbon nanocoils are generated may be taken out from the reaction furnace, and the carbon nanocoils may be separated. The method for separating the carbon nanocoil from the catalyst carrier is not particularly limited. For example, the catalyst carrier is immersed in a hydrofluoric acid, hydrochloric acid, nitric acid, sodium hydroxide solution or the like to dissolve the particulate carrier. A method of taking out the carbon nanocoils, a method of peeling the carbon nanocoils from the support by irradiating ultrasonic waves in an appropriate solvent, and the like can be used.

(II) Carbon Nanocoil Manufacturing Device An embodiment of a carbon nanocoil manufacturing device according to the present invention is described below with reference to FIG. FIG. 1 is a diagram schematically showing a carbon nanocoil manufacturing apparatus according to the present invention.

  As shown in FIG. 1, a carbon nanocoil manufacturing apparatus 100 according to the present invention is provided with a filter 2 in a cylindrical reaction furnace 1 extending in a vertical direction, and a heating device 6 on the outer periphery of the reaction furnace. Is installed along the vertical longitudinal direction of the reactor 1. The reaction furnace 1 is made of a quartz tube, and a quartz flat plate-like filter 2 is fixed by welding so as to bisect the space in the reaction furnace 1 in the vertical direction. The filter 2 has a plurality of holes, and does not pass the catalyst carrier 3 filled thereon, but allows the raw material gas and / or carrier gas supplied from below to pass. The catalyst carrier 3 is filled on the filter 2 so that the catalyst carrier 3 can be held and fluidized on the filter 2. Thus, the catalyst and the raw material gas supplied from below can be brought into contact while the catalyst carrier filled on the filter is caused to flow with the mixed gas passing through the filter. In this manner, the reaction region 4 in which the catalyst carrier is caused to flow and the catalyst and the source gas are brought into contact with each other can be set in the carbon nanocoil manufacturing apparatus 100 according to the present invention.

  Here, the reactor 1 is not limited to a quartz tube, and may be made of other materials. Examples of other materials include metals and ceramics.

  The filter 2 is not limited to quartz, and any material that does not react with the source gas may be used. As the filter 2, for example, metal, ceramics, graphite and the like can be suitably used in addition to quartz.

  The method of installing the filter 2 in the reaction furnace 1 is not limited to welding, and any method may be used as long as the filter 2 can be fixed. As another method for installing the filter, for example, a method of fixing with a screw or the like, a method of fitting into a groove installed in the reaction tube and pressing from the upper part, etc. can be used.

  Further, the shape of the filter 2 is not limited to a flat plate shape, and may be a cage shape as long as the catalyst carrier 3 can be filled thereon.

  The position of the filter 2 is not particularly limited as long as the filter 2 is installed so as to bisect the space in the reaction furnace 1 in the vertical direction. From the viewpoint of securing a reaction region above the filter 2 and securing a gas preheating region for preheating the raw material gas and / or carrier gas supplied to the catalyst carrier 3, the reaction is started from the bottom of the reaction furnace 1. It is preferable to install in the position of 20% to 80% of the length in the longitudinal direction of the furnace 1, more preferably in the position of 30% to 70%, and in the position of 40% to 60%. Further preferred.

  The pore size (pore size) of the filter 2 may be appropriately selected according to the particle size of the catalyst support 3, but is usually from 10 μm to 500 μm.

  In the reaction furnace 1, the catalyst carrier 3 is filled on the filter 2 through the catalyst introduction part 8. The catalyst carrier 3 is formed by carrying a catalyst containing a transition metal on a particulate carrier. Since this catalyst carrier 3 is as described in (I-1) above, the description thereof is omitted here.

  The heating device 6 corresponds to the part corresponding to the reaction region 4 of the reaction furnace 1 and the gas preheating region 5 that is located immediately below the reaction region 4 and preheats the source gas and / or carrier gas supplied to the reaction region. It is arrange | positioned on the outer periphery with a part. As a result, the catalyst carrier 3 filled on the filter 2 can be preheated by the heating device 6, and the reaction region can be reacted while the catalyst carrier is flowed to react the catalyst and the source gas. Can be heated. The heating device 6 may be disposed only on the outer periphery of the portion corresponding to the reaction region 4 of the reaction furnace 1.

  A raw material gas and / or a carrier gas is introduced into the reaction furnace 1 through the gas introduction unit 7, and is supplied through the filter 2 to the catalyst carrier 3 filled on the filter 2.

  The raw material gas and / or carrier gas supplied to the catalyst carrier 3 filled on the filter 2 through the filter 2 is discharged out of the reaction furnace from a gas exhaust unit (not shown).

  The catalyst introduction part 8 is made of a metal catalyst introduction pipe, and the gas introduction part 7 is made of a metal gas introduction pipe. However, the catalyst introduction part 8 and the gas introduction part 7 are not limited to metal, and may be made of other materials such as quartz and ceramics.

  Further, the reaction furnace 1 measures the differential pressure above and below the region filled with the catalyst carrier 3 in the reaction furnace 1 or the differential pressure above and below the filter 2 in a state where the catalyst carrier 3 is not filled. For this purpose, a differential pressure gauge (not shown) may be provided. When the catalyst carrier 3 is filled using a differential pressure gauge, it is installed in the reaction furnace in a state where the catalyst is not filled due to the differential pressure above and below the region filled with the catalyst carrier in the reaction furnace. Carbon nanocoils can be satisfactorily synthesized by filling the catalyst carrier so that the value obtained by subtracting the pressure difference between the top and bottom of the filter is 2 kPa or less after the catalyst is charged and before heating. .

  In the carbon nanocoil manufacturing apparatus according to the present invention, a storage container storing a catalyst carrier 3 to be filled on the filter 2 may be connected to the reaction furnace 1. Further, the measured value of the differential pressure gauge, or the inside of the reactor in a state where the catalyst is not filled from the differential pressure above and below the area filled with the catalyst carrier in the reactor calculated from the measured value. A control device for filling the catalyst carrier 3 on the filter while automatically controlling the amount of the catalyst carrier 3 to be filled according to the value obtained by subtracting the pressure difference between the upper and lower sides of the filter installed in the filter. It may be provided.

  Although this invention is demonstrated more concretely based on an Example, a comparative example, and FIGS. 2-12, this invention is not limited to this. Those skilled in the art can make various changes, modifications, and alterations without departing from the scope of the present invention.

  In the examples and comparative examples, (a) the purity of the carbon nanocoil, (b) the synthesis amount of the carbon nanocoil, (c) the weight of the carbon product, and (d) the difference between the upper and lower regions filled with the catalyst carrier. The value obtained by subtracting the pressure difference between the upper and lower sides of the filter installed in the reactor in the state where the catalyst is not filled from the pressure, and (e) the minimum fluidization rate is measured as follows.

(A) Purity of carbon nanocoil The synthesized catalyst carrier is observed with a scanning electron microscope at a magnification of 1000 to 2000 times, and the number of carbon nanostructures present in the field of view and in the carbon nanostructures The number of carbon nanocoils was counted. This was performed for 10 visual fields, and the ratio of the number of carbon nanocoils to the total number of carbon nanostructures in the entire visual field was defined as the purity of the carbon nanocoils.

(B) Synthesis amount of carbon nanocoil The catalyst carrier on which carbon nanocoils were grown was ultrasonically applied in an organic solvent to peel the carbon nanocoil from the catalyst carrier. The organic solvent containing the catalyst carrier and the peeled carbon nanocoil was passed through a sieve to separate the catalyst carrier that did not pass through the sieve and the organic solvent in which the carbon nanocoil that passed through the sieve was dispersed. The organic solvent in which the carbon nanocoil was dispersed was collected and suction filtered to take out the carbon nanocoil. Thereafter, the weight of the carbon nanocoil was measured using an electronic balance. The measured weight of the carbon nanocoil was changed by the input time of the raw material gas, so that the synthesis amount of carbon nanocoil (unit: g / h) was obtained.

(C) Carbon product weight A value obtained by subtracting the weight of the catalyst carrier before the reaction from the total weight of the catalyst carrier after synthesis of the carbon nanocoil and the generated carbon nanostructure was defined as the carbon product weight. An electronic balance was used for measuring the weight.

(D) The value obtained by subtracting the differential pressure above and below the filter installed in the reactor in the state where the catalyst is not charged from the differential pressure above and below the area filled with the catalyst carrier. Was introduced to the high pressure side of the differential pressure gauge, and the gas exhaust part was branched and introduced to the low pressure side of the differential pressure gauge. While supplying the carrier gas, an electric signal output from the differential pressure gauge was taken into a data logger to measure the differential pressure B above and below the region filled with the catalyst carrier. Further, the differential pressure A above and below the filter installed in the reactor in the state where the catalyst is not filled is separately measured while supplying the same carrier gas at the same gas flow rate as when the differential pressure B is measured, The value of B−A was defined as the differential pressure.

(E) Minimum fluidization speed By changing the gas flow rate of the carrier gas flowing through the reaction furnace, the linear velocity of the carrier gas in the reaction region is changed, and the catalyst carrier in the reaction furnace is filled. The differential pressure B above and below the region was measured for each linear velocity. Similarly to the measurement of the differential pressure B, separately, the differential pressure A above and below the filter installed in the reactor in a state where the catalyst is not filled is measured with respect to each linear velocity. The value of B-A corresponding to the speed was calculated. In the graph in which the B-A values calculated in this manner are plotted against the respective linear velocities, the portion where the B-A values increase linearly as the linear velocity increases, and the B-A values are the linear velocities. With the increase in the linear velocity, the value of the linear velocity at the intersection with the portion showing a constant value was taken as the minimum fluidization velocity.

[Example 1: Production of carbon nanocoil]
In this embodiment, the catalyst carrier is filled on a filter installed inside the reaction furnace and heated, and a mixed gas containing a raw material gas and a carrier gas is supplied from below the filter to the catalyst carrier. A flow state was generated, and carbon nanocoils were manufactured by a CVD reaction.

<Preparation of catalyst carrier>
An ethanol solution containing iron (Fe), indium (In) and tin (Sn) was prepared so that the catalyst composition ratio was Fe: In: Sn = 3: 1: 0.4 in terms of molar ratio, A catalyst solution was obtained.

Specifically, iron nitrate Fe (NO ₃ ) ₃ · 9H ₂ O, indium chloride InCl ₃ and tin chloride SnCl ₄ · 5H ₂ O in a molar ratio of Fe: In: Sn = 3: 1: 0.4 The solution was dissolved in 400 ml of ethanol with stirring to obtain 400 g of a catalyst solution.

  To the obtained catalyst solution, 250 g of alumina particles (average particle size: 78 μm) as a particulate carrier was added. The resulting mixture of alumina particles and catalyst solution was stirred to bring the alumina particle surface into contact with the catalyst solution.

  Thereafter, the alumina particles adhered with the catalyst solution were taken out, heated in a heat resistant container at 800 ° C. for about 1 hour, and cooled to room temperature.

  After cooling, the catalyst carrier was broken into particles to obtain a catalyst carrier.

<Manufacture of carbon nanocoils>
The obtained catalyst carrier was introduced into a reaction furnace, heated, mixed with a raw material gas, and carbon nanocoils were produced by a CVD reaction.

  Specifically, a cylindrical quartz tube (inner diameter: 26 mm, length: 1000 mm, volume: about 0.53 L) is used as a reaction furnace, this quartz tube is arranged vertically, and the center part in the longitudinal direction of the quartz tube ( A quartz filter (pore size: 40 μm) was placed at a position 500 mm from the end. Then, the region of the central portion 400 mm in the longitudinal direction of the quartz tube, that is, the central portion excluding the region of 300 mm from both ends of the quartz tube is used as the reaction region and the gas preheating region, and the outer periphery of the reaction region and the gas preheating region Covered with heating furnace. This reaction furnace is a fluidized bed furnace in which a mixed gas of a raw material gas and a carrier gas is supplied from below the filter so that the catalyst carrier filled on the filter can flow.

  50 g of the catalyst carrier (the pressure difference between the top and bottom of the catalyst carrier was 0.7 kPa) was charged on the filter of the reactor, and He was added from the gas inlet at the bottom of the reactor at the bottom of the filter. It was made to circulate at 2 slm for about 15 minutes, and the catalyst carrier on the filter was made to flow to remove oxygen in the reaction furnace. Here, the differential pressure above and below the catalyst carrier is 0.7 kPa when the catalyst is not filled from the differential pressure above and below the region filled with the catalyst carrier in the reactor. It means that the value obtained by subtracting the pressure difference between the upper and lower sides of the filter installed in the reactor was 0.7 kPa.

  After the oxygen removal was completed, the temperature was raised to 700 ° C. in a state where He was circulated at 1.2 slm, and then the catalyst support was heated by holding at 700 ° C. The total time of the time required for raising the temperature to 700 ° C. and the holding time was 30 minutes.

Thereafter, in a state where the heating device is heated and maintained at 700 ° C., a mixed gas obtained by mixing 0.3 slm of the source gas C ₂ H ₂ with the carrier gas He 1.2 slm is allowed to flow through the gas inlet for 240 minutes to perform CVD. And carbon nanocoils were grown on the catalyst.

  The synthesis amount of the carbon nanocoil was 2 g / 4 hours. The purity of the carbon nanocoil was 80%. Thus, by using the production method of the present invention, as shown in Comparative Example 1 described later, the synthesis amount of carbon nanocoils was 1 g / 4 hours even when a larger reactor having a volume of 35 L was used. Compared with the conventional method, a synthesis amount of 2 g / 4 hours can be secured in a reactor having a volume of about 0.53 L. That is, twice the amount of carbon nanocoils can be synthesized with a volume of about 1.5% of the conventional method.

[Example 2: Production of carbon nanocoil]
A cylindrical quartz tube (inner diameter: 75 mm, length: 1000 mm, volume: about 4.4 L) having a larger inner diameter was used as the reaction furnace, 150 g of the catalyst carrier (the differential pressure above and below the catalyst carrier was 0.3 kPa). The point where the gas used was Ar, and the carrier gas Ar 13.4 slm was mixed with 1.6 slm of the source gas C ₂ H ₂ using a nozzle (mixed). A carbon nanocoil was manufactured in the same manner as in Example 1 except that the linear velocity of the gas was 47 m · sec ⁻¹ (2.8 × 10 ⁵ cm / min).

  Here, the differential pressure above and below the catalyst carrier is 0.3 kPa in the state where the catalyst is not filled from the differential pressure above and below the region filled with the catalyst carrier in the reactor. It means that the value obtained by subtracting the pressure difference between the upper and lower sides of the filter installed in the reactor was 0.3 kPa.

  The synthesis amount of the carbon nanocoil was 8 g / 4 hours. The purity of the carbon nanocoil was 80%. Thus, by using the production method of the present invention, as shown in Comparative Example 1 described later, the synthesis amount of carbon nanocoils was 1 g / 4 hours even when a larger reactor having a volume of 35 L was used. Compared with the conventional method, a synthesis amount of 8 g / 4 hours can be secured in a reactor having a volume of about 4.4 L. That is, an amount of carbon nanocoils that is eight times as large as that of a conventional method can be synthesized with a volume of about 13%.

[Example 3: Production of carbon nanocoil]
A cylindrical quartz tube (inner diameter: 95 mm, length: 1000 mm, volume: about 7.1 L) having a larger inner diameter as a reaction furnace, 450 g of the catalyst support (filled with the catalyst support in the reaction furnace) The value obtained by subtracting the pressure difference between the top and bottom of the filter installed in the reactor in the state where the catalyst is not filled from the pressure difference between the top and bottom of the formed region was 0.65 kPa), the carrier Example except that Ar is used as a gas and a mixed gas obtained by mixing 3.0 slm of the source gas C ₂ H ₂ with the carrier gas Ar27slm (linear velocity of the mixed gas: 0.07 m · sec ⁻¹ ) is used. In the same manner as in No. 1, carbon nanocoils were produced.

  The synthesis amount of the carbon nanocoil was 29.2 g / 2 hours. The purity of the carbon nanocoil was 80%. Thus, by using the production method of the present invention, as shown in Comparative Example 1 described later, the synthesis amount of carbon nanocoils was 1 g / 4 hours even when a larger reactor having a volume of 35 L was used. Compared with the conventional method, a synthesis amount of 29.2 g / 2 hours can be secured in a reactor having a volume of about 7.1 L. That is, 29.2 times the amount of carbon nanocoils can be synthesized with a volume of about 20% of the conventional method.

[Comparative Example 1: Production of carbon nanocoil by conventional substrate method]
A catalyst was coated on the heat-resistant substrate surface to prepare a catalyst-coated substrate. The prepared catalyst-coated substrate was placed in a reaction tube and heated, and a raw material gas was supplied to bring the catalyst on the surface of the catalyst-coated substrate into contact with the raw material gas, thereby producing carbon nanocoils on the surface of the catalyst-coated substrate by a CVD reaction.

  Specifically, about half the volume of the 35 L reaction tube was maintained at 700 ° C., and synthesis was performed using 2500 L of inert gas and 110 L of raw material gas until the completion of the reaction. As a result, the synthesis amount of the carbon nanocoil was 1 g / 4 hours.

[Example 4: Influence of linear velocity of mixed gas on synthesis amount of carbon nanocoil]
In order to investigate the influence of the linear velocity of the mixed gas on the synthesis amount of the carbon nanocoil, the carbon nanocoil was synthesized by changing the linear velocity of the mixed gas.

<Example 4-1>
A catalyst carrier was produced in the same manner as in Example 1. The catalyst was prepared in the same manner as in Example 1 except that 100 g of the obtained catalyst carrier was charged and that a mixed gas obtained by mixing 0.075 slm of the raw material gas C ₂ H ₂ was circulated into the carrier gas He 0.675 slm. Carbon nanocoils were grown on top.

<Example 4-2>
Carbon nanocoils were grown on the catalyst in the same manner as in Example 4-1, except that a mixed gas obtained by mixing 0.15 slm of the raw material gas C ₂ H ₂ was passed through the carrier gas He 1.35 slm.

<Example 4-3>
Carbon nanocoils were grown on the catalyst in the same manner as in Example 4-1, except that a mixed gas obtained by mixing 0.3 slm of the raw material gas C ₂ H ₂ was passed through the carrier gas He 2.7 slm.

<Example 4-4>
A cylindrical quartz tube (inner diameter: 75 mm, length 1000 mm) having a larger inner diameter was used as the reaction furnace, except that a mixed gas in which 3 slm of the source gas C ₂ H ₂ was mixed with the carrier gas He 27 slm was circulated. Carbon nanocoils were grown on the catalyst in the same manner as in Example 4-1.

<Example 4-5>
A cylindrical quartz tube (inner diameter: 75 mm, length 1000 mm) having a larger inner diameter was used as a reaction furnace, and a mixed gas obtained by mixing 1.6 slm of source gas C ₂ H ₂ with carrier gas He 13.4 slm Carbon nanocoils were grown on the catalyst in the same manner as in Example 4-1, except that they were used and distributed.

<Example 4-6>
A cylindrical quartz tube (inner diameter: 95 mm, length: 1000 mm) having a larger inner diameter is used as a reaction furnace, except that a mixed gas in which a source gas C ₂ H ₂ is mixed with 3.0 slm is circulated in a carrier gas He 27 slm. In the same manner as in Example 4-1, carbon nanocoils were grown on the catalyst.

  In Table 1 below, for Examples 4-1 to 4-6, the supplied carrier gas, raw material gas, and gas flow rate of the mixed gas, the inner diameter and cross-sectional area of the quartz tube, the linear velocity of the mixed gas, the carbon nanocoil The amount of synthesis (g / h) is shown. In addition, the peeling of the catalyst from the particulate carrier is shown in large and small amounts. The gas flow rate of the mixed gas is a value described in the column “Total (mixed gas)” of “Gas flow rate” in Table 1.

  The exfoliation of the catalyst from the particulate support was evaluated by bubbling the exhaust gas from the reaction furnace in ethanol and visually observing the amount of the catalyst exfoliated from the particulate support. When the ethanol solution turned red due to the peeled catalyst, the catalyst was peeled off a lot, and when the ethanol solution was slightly red, the catalyst was peeled off a little.

  Moreover, in FIG. 2, the results of observing the carbon nanocoils generated on the catalyst of the catalyst carrier at a low magnification with a scanning electron microscope for Examples 4-1 4-2, and 4-3 (in FIG. 2, (A), (b), and (c)) and the results observed at high magnification ((d), (e), and (f), respectively, in FIG. 2) are shown.

  Moreover, about Example 4-4, 4-5, and 4-6 in FIG. 3, the result of having observed the carbon nano coil produced | generated on the catalyst of the catalyst support body by the scanning electron microscope at low magnification (in FIG. 3, respectively) , (A), (b) and (c)) and the results observed at high magnification ((d), (e) and (f) in FIG. 3 respectively) are shown.

As can be seen from Table 1, the linear velocity of the mixed gas is ^{0.02m · sec -1, 0.05m · sec} -1, 0.07m · sec -1, 0.09m · sec -1, 0.11m · sec It can be seen that carbon nanocoils can be produced at ⁻¹ and 47 m · sec ⁻¹ .

[Example 5: Differential pressure above and below the area filled with the catalyst carrier]
In this example, the upper and lower differential pressures in the region filled with the catalyst carrier were measured.

<Example 5-1>
A catalyst carrier was prepared in the same manner as in Example 1. In the same manner as in Example 1, 50 g of the obtained catalyst carrier was filled on the filter of the reaction furnace, and then the carrier gas He was supplied and the gas flow rate was changed while changing the gas flow rate. The upper and lower differential pressures were measured.

The measurement results are shown in FIG. In FIG. 4, the vertical axis represents a value obtained by subtracting the differential pressure above and below the filter installed in the reactor in the state where the catalyst is not filled from the differential pressure above and below the area filled with the catalyst carrier (B -A) (unit: kPa), and the horizontal axis indicates the linear velocity of the carrier gas He (described as “Flow rate” in FIG. 4, unit: m · sec ⁻¹ ). As shown in FIG. 4, the differential pressure above and below the region filled with the catalyst carrier was 1 kPa or less after heating and before heating.

<Example 5-2>
A catalyst carrier was prepared in the same manner as in Example 1. After 150 g of the obtained catalyst carrier is filled on the filter of the reactor used in Example 2, the carrier gas Ar is supplied, and the gas flow rate is changed while changing the upper and lower sides of the region filled with the catalyst carrier. The differential pressure was measured. Next, the same measurement was performed when the amount of the catalyst support filled on the filter of the reactor used in Example 2 was 300 g and 450 g.

The measurement results are shown in FIG. In FIG. 5 (a), the vertical axis is obtained by subtracting the differential pressure above and below the filter installed in the reactor in a state where the catalyst is not filled from the differential pressure above and below the area filled with the catalyst carrier. The value (BA) (unit: kPa) is shown, and the horizontal axis shows the linear velocity of carrier gas Ar (described as “Flow rate” in FIG. 5A, unit: m · sec ⁻¹ ). As shown in FIG. 5A, the upper and lower differential pressures in the region filled with the catalyst carrier were 1 kPa or less after the catalyst was charged and before the heating.

<Example 5-3>
A catalyst carrier was prepared in the same manner as in Example 1. After 450 g of the obtained catalyst carrier is filled on the filter of the reactor used in Example 3, the carrier gas Ar is supplied, and the gas flow rate is changed while changing the gas flow rate. The differential pressure was measured. Next, the same measurement was performed when the amount of the catalyst carrier filled on the filter of the reactor used in Example 3 was 900 g.

The measurement results are shown in FIG. In FIG. 5 (b), the vertical axis is obtained by subtracting the differential pressure above and below the filter installed in the reactor in a state where the catalyst is not filled from the differential pressure above and below the area filled with the catalyst carrier. The value (BA) (unit: kPa) is shown, and the horizontal axis shows the linear velocity of the carrier gas Ar (“Flow rate” and description unit: m · sec ^{−1 in} FIG. 5B). As shown in FIG. 5B, the upper and lower differential pressures in the region filled with the catalyst carrier were 2 kPa or less after the catalyst was charged and before the heating.

[Example 6: Temperature in the reactor]
<Example 6-1>
A catalyst carrier was produced in the same manner as in Example 1. Using the obtained catalyst carrier, carbon nanocoils were grown on the catalyst in the same manner as in Example 2 except that the gas flow rate of the mixed gas was 15 slm. At this time, the temperature of the reaction region in the reaction furnace was measured. The temperature of the reaction region in the reaction furnace was measured by inserting a thermocouple at a position 10 mm above the filter in the furnace.

  The temperature of the reaction region in the reaction furnace was in the range of 700 ° C. to 770 ° C., and carbon nanocoils could be suitably manufactured.

<Example 6-2>
Iron (Fe), instead of using the metal ethanol solution of indium (In) and tin (Sn), iron nitrate _{Fe (NO 3) 3 · 9H} 2 O and tin chloride SnCl ₄ · 5H ₂ O, in a molar ratio, A catalyst carrier was produced in the same manner as in Example 1 except that 400 g of the catalyst solution was obtained by dissolving in 400 ml of ethanol while stirring so that Fe: Sn = 10: 1.

  Using the obtained catalyst carrier, carbon nanocoils were grown on the catalyst in the same manner as in Example 2, except that the gas flow rate of the mixed gas was 10 slm, 15 slm, or 22.4 slm. About the gas flow rate of each mixed gas, it carried out similarly to Example 6-1, and measured the temperature of the reaction area | region in a reaction furnace.

  The temperature of the reaction region in the reaction furnace was in the range of 700 ° C. to 770 ° C., and carbon nanocoils could be suitably manufactured.

[Example 7: Production of carbon nanocoils using various catalysts]
<Example 7-1>
Iron (Fe), instead of using an ethanol solution containing indium (In) and tin (Sn), iron nitrate _{Fe (NO 3) 3 · 9H} 2 O and tin chloride SnCl ₄ · 5H ₂ O, in a molar ratio, A catalyst carrier was produced in the same manner as in Example 1 except that 400 g of the catalyst solution was obtained by dissolving in 400 ml of ethanol while stirring so that Fe: Sn = 2: 1.

  Carbon nanocoils were produced in the same manner as in Example 1 except that the catalyst carrier obtained as described above was used.

  The result of having observed the carbon nano coil produced | generated on the catalyst with the field emission type | mold scanning electron microscope (FE-SEM) is shown to (a) of FIG. As shown in FIG. 6 (a), the carbon nanocoil was successfully manufactured.

<Example 7-2>
Except that the catalyst solution was prepared so that the molar ratio of Fe and Sn in the catalyst was Fe: Sn = 10: 1, a catalyst carrier was produced in the same manner as in Example 7-1 to produce carbon nanocoils. did.

  The result of having observed the carbon nano coil produced | generated on the catalyst with the field emission type | mold scanning electron microscope (FE-SEM) is shown in FIG.6 (b). As shown in FIG. 6B, the carbon nanocoil was successfully manufactured.

<Example 7-3>
Except that the catalyst solution was prepared so that the molar ratio of Fe and Sn in the catalyst was Fe: Sn = 20: 1, a catalyst carrier was produced in the same manner as in Example 7-1 to produce carbon nanocoils. did.

  The result of having observed the carbon nano coil produced | generated on the catalyst with the field emission type | mold scanning electron microscope (FE-SEM) is shown to (c) of FIG. As shown in FIG. 6 (c), the carbon nanocoil was successfully manufactured.

<Example 7-4>
Except that the catalyst solution was prepared so that the molar ratio of Fe and Sn in the catalyst was Fe: Sn = 30: 1, a catalyst carrier was produced in the same manner as in Example 7-1 to produce carbon nanocoils. did.

  The result of observing the carbon nanocoil produced on the catalyst with a field emission scanning electron microscope (FE-SEM) is shown in FIG. As shown in FIG. 6 (d), the carbon nanocoil was successfully manufactured.

<Example 7-5>
A catalyst carrier was produced in the same manner as in Example 1. Carbon nanocoils were produced in the same manner as in Example 1 using the obtained catalyst support.

  FIG. 7A shows the result of observing the carbon nanocoil generated on the catalyst with a field emission scanning electron microscope (FE-SEM). As shown in FIG. 7 (a), the purity of the carbon nanocoil was greater than 80%, and the carbon product weight was 15.7 g. Carbon nanocoils could be manufactured very well.

<Example 7-6>
Iron nitrate Fe (NO ₃ ) ₃ · 9H ₂ O, indium chloride InCl ₃ and tin chloride SnCl ₄ · 5H ₂ O in a molar ratio of Fe: In: Sn = 3: 1: 0.3, A catalyst carrier was produced in the same manner as in Example 1 except that 400 g of catalyst solution was obtained by dissolving in 400 ml of ethanol while stirring.

  Carbon nanocoils were produced in the same manner as in Example 1 except that the catalyst carrier obtained as described above was used. The carbon nanocoil was successfully manufactured.

<Example 7-7>
A catalyst carrier in the same manner as in Example 7-6 except that the catalyst solution was prepared so that the molar ratio of Fe, In, and Sn in the catalyst was Fe: In: Sn = 3: 1: 0.6. To produce carbon nanocoils.

  FIG. 7B shows the result of observing the carbon nanocoil generated on the catalyst with a field emission scanning electron microscope (FE-SEM). As shown in FIG. 7B, the purity of the carbon nanocoil was greater than 80%, and the carbon product weight was 13.3 g. Carbon nanocoils could be manufactured very well.

<Example 7-8>
A catalyst carrier in the same manner as in Example 7-6 except that the catalyst solution was prepared so that the molar ratio of Fe, In, and Sn in the catalyst was Fe: In: Sn = 3: 1: 0.8. To produce carbon nanocoils.

  The result of having observed the carbon nano coil produced | generated on the catalyst with the field emission scanning electron microscope (FE-SEM) is shown in FIG.7 (c). As shown in FIG. 7 (c), the carbon nanocoil was successfully manufactured.

<Example 7-9>
A catalyst carrier was produced in the same manner as in Example 7-6 except that the catalyst solution was prepared so that the molar ratio of Fe, In, and Sn in the catalyst was Fe: In: Sn = 3: 1: 1. Carbon nanocoils were manufactured.

  The result of observing the carbon nanocoil produced on the catalyst with a field emission scanning electron microscope (FE-SEM) is shown in FIG. As shown in FIG. 7D, carbon nanocoils could be manufactured.

<Example 7-10>
A catalyst carrier in the same manner as in Example 7-6 except that the catalyst solution was prepared so that the molar ratio of Fe, In, and Sn in the catalyst was Fe: In: Sn = 3: 2: 0.4. To produce carbon nanocoils.

  The result of observing the carbon nanocoil produced on the catalyst with a field emission scanning electron microscope (FE-SEM) is shown in FIG. As shown in FIG. 7E, carbon nanocoils could be manufactured.

  Table 2 below shows the results of Example 7-5 to Example 7-10. Table 2 shows the production state of carbon nanocoils when the amount of Fe contained in the catalyst is 3 in terms of moles and the amounts of Sn and In are changed. In Table 2, the production state of the carbon nanocoil is ◎ when the synthesis of the carbon nanocoil is very good, that is, when the purity is 80% or more and the carbon product weight is 7.5 g or more. The production state of carbon nanocoils is ◯ when the synthesis of carbon nanocoils is good, that is, when the purity is 80% or more and the carbon product weight is 4 g or more. The coil production state is Δ means that the carbon nanocoil can be synthesized, that is, the purity is 10% or more and the carbon product weight is 2 g or more.

[Example 8: Effect of particle size distribution of particulate carrier on carbon nanocoil production]
<Example 8-1>
In Example 1, alumina particles having an average particle diameter of 78 μm were used as the particulate carrier for supporting the catalyst. The particle size distribution of the alumina particles used is shown in FIG. As shown in FIG. 8 (a), the particulate carrier used had a narrow particle size distribution and a relative standard deviation of the particle size of 12% or less.

  FIG. 8B shows the result of observation of carbon nanocoils having an average length among the obtained carbon nanocoils with a scanning electron microscope. Table 3 shows the average length of carbon nanocoils obtained in this example and the weight of the carbon product.

  As shown in FIG. 8B and Table 3, the average length of the obtained carbon nanocoil was 18 μm.

<Example 8-2>
A catalyst support was prepared in the same manner as in Example 1 except that alumina particles having an average particle size of 49 μm and a larger particle size distribution were used as the particulate support for supporting the catalyst. Nanocoils were manufactured. The particle size distribution of the alumina particles used is shown in FIG. As shown in FIG. 9 (a), the particulate carrier used had two distributions around 20 μm and 70 μm, and the relative standard deviation of the particle diameter was 64% or less.

  The result of having observed the carbon nanocoil which has average length among the carbon nanocoils obtained by FIG.9 (b) with the scanning electron microscope is shown. Table 3 shows the average length of carbon nanocoils obtained in this example and the weight of the carbon product.

  As shown in FIG. 9B and Table 3, the average length of the obtained carbon nanocoil was 5.7 μm.

[Example 9: Influence of catalyst loading ratio on production of carbon nanocoil]
<Preparation of catalyst carrier>
Carbon nanocoils were manufactured using catalyst carriers having various catalyst loadings. The preparation of the catalyst carrier having a changed catalyst loading rate was performed by changing the concentration of the metal salt dissolved in ethanol in the method for preparing the catalyst carrier of Example 1.

  Specifically, except that the concentration of the metal salt dissolved in ethanol was changed, the catalyst loading was 0.02% by weight, 0.12% by weight, 0.33% by weight, as in Example 1. And 0.56 weight% of catalyst support body was prepared.

<Example 9-1>
Carbon nanocoils were produced in the same manner as in Example 1 except that the catalyst carrier having a catalyst loading rate of 0.02% by weight prepared as described above was used. The minimum fluidization speed of the catalyst carrier at this time was 0.03 m · sec ⁻¹ . Table 4 below shows the state of carbon nanocoil generation.

<Example 9-2>
Carbon nanocoils were produced in the same manner as in Example 1 except that the catalyst carrier having a catalyst loading of 0.12% by weight prepared as described above was used. The minimum fluidization speed of the catalyst carrier at this time was 0.03 m · sec ⁻¹ . Table 4 below shows the state of carbon nanocoil generation.

<Example 9-3>
Carbon nanocoils were produced in the same manner as in Example 1 except that the catalyst carrier having a catalyst loading rate of 0.33% by weight prepared as described above was used. The minimum fluidization speed of the catalyst carrier at this time was 0.03 m · sec ⁻¹ . Table 4 below shows the state of carbon nanocoil generation.

<Example 9-4>
Carbon nanocoils were produced in the same manner as in Example 1 except that the catalyst carrier having a catalyst loading of 0.56% by weight prepared as described above was used. The minimum fluidization speed of the catalyst carrier at this time was 0.03 m · sec ⁻¹ . Table 4 below shows the state of carbon nanocoil generation.

<Example 9-5>
A carbon nanocoil was produced in the same manner as in Example 2 except that the catalyst carrier having a catalyst loading of 0.56% by weight prepared as described above was used, and the amount charged into the reactor was 150 g. . At this time, the minimum fluidization speed of the catalyst carrier at this time was 0.02 m · sec ⁻¹ . Table 4 below shows the state of carbon nanocoil generation.
<Example 9-6>
A carbon nanocoil was produced in the same manner as in Example 3 except that the catalyst carrier having a catalyst loading ratio of 0.56% by weight prepared as described above was used, and the amount charged into the reactor was 450 g. . The minimum fluidization speed of the catalyst carrier at this time was 0.02 m · sec ⁻¹ . Table 4 below shows the state of carbon nanocoil generation.

As shown in Table 4, when the minimum fluidization speed of the catalyst support is 0.03 m · sec ⁻¹ , the catalyst is fixed in the reactor when the catalyst support is 0.02 wt% and 0.12 wt%. No carbon nanocoil could be produced satisfactorily.

Further, when the minimum fluidization speed of the catalyst carrier is 0.02 m · sec ⁻¹ , even in the case where the catalyst loading rate is 0.56 wt%, there is no sticking in the reaction furnace, and the carbon nanocoil is manufactured satisfactorily. We were able to.

  FIG. 10 shows the results of observation of the carbon nanocoils produced on the catalyst of the catalyst carrier with a scanning electron microscope at a low magnification for Examples 9-1 and 9-2 ((a) in FIG. 10). And (b)) and the result ((c) and (d) in FIG. 10) observed at high magnification are shown. In FIG. 10, (a) and (c) show the observation results for Example 9-1, and (b) and (d) show the observation results for Example 9-2. FIG. 11 shows the results of observation of the carbon nanocoils generated on the catalyst of the catalyst carrier with a scanning electron microscope at a low magnification for Examples 9-3 and 9-4 ((a) in FIG. 11). And (b)) and the results observed in high magnification ((c) and (d) in FIG. 11) are shown. In FIG. 11, (a) and (c) show the observation results for Example 9-3, and (b) and (d) show the observation results for Example 9-4.

  By using the carbon nanocoil manufacturing method and manufacturing apparatus of the present invention, high-purity carbon nanocoils can be efficiently synthesized in a shorter time than conventional methods, and mass synthesis of carbon nanocoils can be realized. Therefore, the present invention can be used not only in the carbon nanocoil manufacturing industry, but also in the electronic equipment manufacturing industry for manufacturing various products incorporating the carbon nanocoil, and is very useful. It is believed that there is.

DESCRIPTION OF SYMBOLS 1 Reaction furnace 2 Filter 3 Catalyst support body 4 Reaction area | region 5 Gas preheating area | region 6 Heating device 7 Gas introduction part 8 Catalyst introduction part 100 Carbon nanocoil manufacturing apparatus

Claims (17)

A catalyst filling step of filling a particulate carrier with a catalyst carrier comprising a catalyst containing a transition metal on a filter installed in a cylindrical reaction furnace extending in the vertical direction;
While heating the catalyst carrier, the mixed gas containing the raw material gas and the carrier gas is supplied from below the filter through the filter, and the catalyst carrier is fluidized with the mixed gas passing through the filter. And a carbon nanocoil synthesizing step of growing carbon nanocoils on the catalyst by contacting the raw material gas with the raw material gas.   The method for producing carbon nanocoils according to claim 1, wherein the reaction furnace is a reaction furnace in which the filter is installed so as to bisect the space in the reaction furnace in the vertical direction. 3. The method for producing a carbon nanocoil according to claim 1, wherein the linear velocity of the mixed gas is controlled to 0.01 m · sec ⁻¹ or more and 50 m · sec ⁻¹ or less.   The value obtained by subtracting the differential pressure above and below the filter installed in the reactor in a state where the catalyst is not filled from the differential pressure above and below the region filled with the catalyst carrier in the reactor is the catalyst. The method for producing a carbon nanocoil according to any one of claims 1 to 3, wherein the catalyst carrier is filled so as to be 2 kPa or less after filling and before heating.   The method for producing carbon nanocoils according to any one of claims 1 to 4, wherein a catalyst carrier having an average particle diameter of 10 µm or more and 1 mm or less is used as the catalyst carrier.   The method for producing carbon nanocoils according to any one of claims 1 to 5, wherein a monodispersed catalyst carrier is used as the catalyst carrier. The catalyst carrier is filled so that the minimum fluidization speed of the catalyst carrier is less than 0.03 m · sec ⁻¹ after the catalyst filling and before heating, and the catalyst carrier is used as the catalyst carrier. 7. The method for producing carbon nanocoils according to claim 1, wherein a catalyst carrier having a content of 0.01 wt% or more and 0.6 wt% or less is used. The catalyst carrier is filled so that the minimum fluidization speed of the catalyst carrier is 0.03 m · sec ⁻¹ or more after the catalyst is charged and before heating, and the catalyst carrier is used as the catalyst carrier. 7. The method for producing carbon nanocoils according to claim 1, wherein a catalyst carrier having a content of 0.01 wt% or more and 0.3 wt% or less is used.   Using a reactor equipped with a heating device on the outer periphery, the catalyst carrier filled on the filter is caused to flow in a heating region heated by the heating device to contact the catalyst and the source gas. The method for producing carbon nanocoils according to claim 1, wherein the carbon nanocoil is set so as to include a reaction region.   Using a reactor equipped with a heating device on the outer periphery, the catalyst carrier filled on the filter is caused to flow in a heating region heated by the heating device to contact the catalyst and the source gas. The carbon nanometer according to any one of claims 1 to 8, wherein the carbon nanometer according to any one of claims 1 to 8 is set so as to include a reaction region to be heated and a gas preheating region for heating the carrier gas and / or the raw material gas before passing through the filter. Coil manufacturing method.   The temperature of the reaction zone in which the catalyst carrier packed on the filter is made to flow and the catalyst and the source gas are brought into contact is 600 ° C. or higher and 850 ° C. or lower, and the temperature of the gas preheating region is 300 ° C. or higher. It controls to 850 degrees C or less, The manufacturing method of the carbon nano coil of any one of Claims 1-10 characterized by the above-mentioned.   The method for producing carbon nanocoils according to any one of claims 1 to 11, wherein a catalyst containing at least Fe and Sn is used as the catalyst.   13. The method for producing carbon nanocoils according to claim 12, wherein a catalyst having a molar ratio of Fe to Sn of 2 ≦ Fe / Sn ≦ 30 is used as the catalyst.   The method for producing carbon nanocoils according to claim 12 or 13, wherein a catalyst containing In is further used as the catalyst.   The catalyst is characterized in that a molar ratio of Fe and Sn is 2 ≦ Fe / Sn ≦ 30 and a molar ratio of In and Sn is 0 ≦ In / Sn ≦ 30. The method for producing a carbon nanocoil according to claim 14.   The method for producing carbon nanocoils according to any one of claims 1 to 15, wherein an oxide is used as the catalyst. A cylindrical reaction furnace having a filter installed therein and extending in the vertical direction, the reaction furnace having a reaction region filled with a catalyst carrier on the filter;
A heating device installed at least in the outer periphery of the reaction region of the reactor;
A gas introduction section for supplying a raw material gas and / or a carrier gas from below the filter of the reactor through the filter;
A carbon nanocoil manufacturing apparatus characterized by comprising: