JP3949594B2 - Fullerene isolation method and apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention, from a solution of fullerenes containing C ₆₀ and C _70, a method of isolating a C ₆₀ is a specific fullerene.
[0002]
[Prior art]
As a method for isolating and recovering fullerene C ₆₀ from a fullerene raw material containing various fullerenes having different molecular weights obtained from a normal combustion method or arc method, there are a stationary phase using an adsorbent and a mobile phase which is an eluent. The chromatographic isolation method based on the principle of contact is the mainstream, and a method of sequentially extracting by utilizing the solubility difference of each fullerene with respect to a specific solvent is also known.
For example, Patent Document 1 also discloses a method for continuously separating and purifying a fullerene mixture in large quantities.
[0003]
[Patent Document 1]
Japanese Patent No. 3134414 [0004]
[Problems to be solved by the invention]
However, in the chromatographic isolation method, since the adsorbent must be regenerated and / or exchanged, it is impossible to perform continuous isolation and it is difficult to scale up the column. There was a problem that it was not suitable.
On the other hand, in the dissolution method using the difference in solubility, it is known that the fullerene crystal obtained by one treatment is a solid solution, and its purity is governed by the solid-liquid equilibrium. The same treatment must be performed again, and there is a problem that the recovery rate is extremely lowered and is not industrially suitable.
Furthermore, in patent document 1, since the vapor pressure of fullerene itself was low, there existed a problem of requiring enormous energy.
[0005]
The present invention has been made in view of such circumstances, and an object thereof is to provide a method for isolating and apparatus of fullerene that apart continuous single without requiring a great deal of energy to specific fullerene consisting C ₆₀ on an industrial scale .
[0006]
[Means for Solving the Problems]
In the isolation method of fullerene according to the first invention that meets the above-mentioned object, when isolating a specific fullerene from fullerenes, a fullerene other than the specific fullerene is preferentially taken into a physical phase preferentially taking in the fullerene. Specific fullerenes with increased purity are obtained by bringing the physical phase into countercurrent contact.
Here, fullerenes refer to, for example, mixed fullerenes containing several types of fullerenes having different molecular weights obtained by a normal combustion method or an arc method.
Isolation means that only one substance is removed from a mixture in a pure form, but also includes a case in which the substance is removed in a nearly pure form.
Further, the countercurrent contact refers to contact in an opposed flow. Here, the precipitated crystals and the rising solvent come into contact with each other in a reverse flow.
[0007]
In the dissolution method using the solubility difference of fullerene, it is known that fullerene crystals are solid solution, and the purity is known to be governed by solid-liquid equilibrium. When the physical phase to be incorporated is a solid and the physical phase to preferentially capture fullerenes other than the specific fullerene is a liquid, the specific fullerene exists not only in the solid but also in the liquid. However, fullerenes other than specific fullerenes are also present.
In addition, when fullerenes are crystallized, pure specific fullerene (C ₆₀ ) cannot be obtained by one crystallization, and in order to obtain pure specific fullerene, it is necessary to repeat crystallization many times. It can be seen that not only the specific fullerene but also other fullerenes are present in the crystal of the specific fullerene obtained by crystallization.
Therefore, when a specific fullerene is preferentially taken in and a liquid that is a physical phase preferentially incorporating a fullerene other than a specific fullerene is brought into contact with a solid that is also a physical phase containing a fullerene other than a specific fullerene, the specific in the solid is identified. Fullerenes other than fullerenes preferentially move toward the liquid phase.
As a result, the purity of the specific fullerene in the solid is remarkably improved.
[0008]
The physical phase that preferentially captures fullerenes other than the specific fullerene is preferably used in order to capture fullerenes other than the specific fullerene in an equilibrium state, so that it contains almost no fullerene other than the specific fullerene.
Moreover, although solid and liquid were demonstrated here, when a physical phase is gas or a liquid, it is thought that a principle is substantially the same.
[0009]
Therefore, the physical phase that preferentially takes in the specific fullerene and the physical phase that preferentially takes in fullerenes other than the specific fullerene may be any combination of gas and liquid, liquid and liquid, solid and liquid, and solid and gas phase. It is also possible to apply the specific fullerene in any phase.
Here, the solid phase (solid phase) is a specific fullerene, a mixed fullerene, a solvation of a single fullerene, a solvation of a mixed fullerene, a phase containing a substance that adsorbs fullerene or promotes solidification of fullerene, such as an adsorbent. Or 1 or 2 or more.
The liquid phase (liquid phase) refers to a solution state phase containing a solvent since fullerene does not exist as a liquid.
The gas phase (gaseous phase) includes specific fullerenes alone, mixed fullerene vapors and / or gases. However, this gas is preferably an inert gas in order to avoid a reaction with fullerene (for example, oxidation).
[0010]
In the method for isolating fullerene according to the second invention, specific fullerene having reached saturation solubility is preferentially precipitated from a concentrated solution obtained by heating a solution of fullerenes to evaporate and remove the solvent, By isolating contact with a solvent preferentially dissolving fullerenes other than the specific fullerene, the purity of the specific fullerene is increased and isolated.
Here, since the fullerenes are dissolved in a solvent that preferentially dissolves fullerenes other than the specific fullerene to form a solution, when the solvent is evaporated and the solution is concentrated, the specific fullerene having low solubility is saturated. And preferentially precipitate. The precipitated crystals are not crystals with a specific fullerene purity of 100% but contain fullerenes other than specific fullerenes. By bringing this crystal into contact with a solvent that preferentially dissolves fullerenes other than specific fullerenes, Fullerenes other than the specific fullerene flow into the solvent, and the purity of the specific fullerene in the crystal is increased.
Note that the solvent for dissolving the fullerenes and the solvent for countercurrent contact with the specific fullerene crystals may be the same, or another solvent may be used.
It is preferable to use the same solvent because using the same solvent allows a continuous series of operations.
[0011]
The fullerene isolation method according to the third aspect of the invention is that a fullerene solution is placed in a crystallization tower comprising a vertically long container, and the upper part of the crystallization tower is heated to evaporate and remove the solvent at the upper part of the crystallization tower. The specific fullerene is preferentially precipitated and settled at the bottom of the crystallization tower, and the solvent removed by evaporation is condensed in a condenser, and part or all of the solvent is returned to the bottom of the crystallization tower. By generating an upward flow in the crystallization tower, the crystal phase and the solvent phase are brought into countercurrent contact, and the purity of the specific fullerene in the crystal phase is increased and isolated.
Since the crystallization tower containing the fullerene solution is a vertically long vessel, while the specific fullerene deposited preferentially settles at the bottom, this crystalline phase is in countercurrent contact with the solvent generated in the crystallization tower. By doing so, the crystal | crystallization which settled to the lower part has the high purity of specific fullerene.
[0012]
A fullerene isolation method according to a fourth invention is the fullerene isolation method according to the third invention, wherein a solution of fullerenes is continuously supplied from an intermediate portion of the crystallization tower, and the crystallization tower is The specific fullerene is taken out from the lower part. Here, the specific fullerene may be taken out in any state of a solution, a crystal, and a solid-liquid mixed phase.
In the lower part of the crystallization tower, crystals with high specific fullerene purity are dissolved in a solvent to form a solution. The fullerene solution is continuously taken out, and fullerenes are continuously extracted from the middle part of the crystallization tower. Thus, fullerene can be continuously isolated from fullerenes by keeping the amount of the solution in the crystallization tower substantially constant.
[0013]
The fullerene isolation method according to the fifth invention is the fullerene isolation method according to the third and fourth inventions, wherein the fullerenes mainly comprise C ₆₀ and C ₇₀ , and the specific fullerene is formed from the lower part of the crystallization tower. solution of C ₆₀ mainly is, are extracted solution consisting mainly of C ₇₀ from the top of the crystal析塔.
It can be prevented from becoming higher the concentration of C ₇₀ in the solution by extracting the solution consisting mainly of C ₇₀ from the top of the crystal析塔.
[0014]
The fullerene isolation method according to a sixth aspect of the present invention is the fullerene isolation method according to the second to fifth aspects of the present invention, wherein the solvent is an aromatic hydrocarbon.
As shown in FIG. 3 showing the solubility of fullerenes in o-xylene (ortho-xylene), which is an example of aromatic hydrocarbons, aromatic hydrocarbons are C ₆₀ and a specific fullerene to be isolated. difference in solubility between the C ₇₀ is a fullerene other than the specific fullerene is very large. Accordingly, C ₆₀ is preferentially crystallized in the solvent, and the purity of C ₆₀ can be increased by bringing the o-xylene solution into contact with the crystallized C ₆₀ again.
In addition to o-xylene, which is an example of an aromatic hydrocarbon, the solvent has high solubility in fullerenes other than specific fullerenes and has low solubility in specific fullerenes, for example, 1,2,4, -trimethylbenzene It is preferable to use aromatic hydrocarbons such as
In addition, the solvent used in the second to fifth inventions is preferentially precipitated because the specific fullerene to be isolated by the combination of the composition of the mixed fullerene and the operation temperature during concentration first becomes saturated in the solution. Any aromatic hydrocarbon may be used as long as it is a solvent to be used.
[0015]
A fullerene isolation device according to a seventh invention is an apparatus for isolating a specific fullerene from a solution of fullerenes in which fullerenes having different molecular weights are dissolved,
A crystallization tower comprising a vertically long container having a heating part for heating the solution to vaporize the solvent, a solution supply means for supplying the solution as a raw material to an intermediate part of the crystallization tower, and the crystal A condenser for extracting and liquefying the vaporized solvent discharged from the top of the crystallization tower; a solvent supply means for supplying the solvent liquefied by the condenser to the lower part of the crystallization tower; and a specific fullerene having low solubility. Specific fullerene extraction means for extracting from the lower part of the crystallization tower, and solution extraction means for extracting a solution of fullerenes other than the specific fullerene from the upper part of the crystallization tower.
[0016]
The fullerene isolation device according to an eighth aspect of the present invention is the fullerene isolation device according to the seventh aspect of the invention, wherein the crystallization tower purifies the crystallized portion of the specific fullerene in the upper part and crystals that settle below it. It has a cylindrical part of sufficient length.
The specific fullerene crystals crystallized in the upper crystallization part of the crystallization tower are purified by countercurrent contact with the solvent during settling because the lower cylindrical part has a sufficient length.
Moreover, it is preferable that the crystallization part is expanded in diameter so that the crystal of the specific fullerene is precipitated and the solvent is sufficiently evaporated.
[0017]
A fullerene isolation device according to a ninth invention is the fullerene isolation device according to the seventh and eighth inventions, wherein a stirring means for stirring the introduced solution is provided at an upper portion of the crystallization tower. And a level sensor for controlling the liquid level at the top of the crystallization tower is provided, connected to any one or more of the solution supply means, the specific fullerene extraction means, and the solution extraction means, Liquid level control is performed.
Since the stirring means is provided at the top of the crystallization tower, the crystallization reaction of the specific fullerene can be promoted. Further, a level sensor for controlling the liquid level is provided, and the solution supply means and the specific fullerene are extracted. Since the liquid level control is performed in connection with one or more of the means and the solution extraction means, continuous processing is possible while maintaining a constant liquid amount.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
FIG. 1 is an explanatory diagram showing a schematic configuration of a fullerene isolation device according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of a fullerene isolation method using the same device, and FIG. 3 is a solvent. It is explanatory drawing about the performance of the orthoxylene to be used.
[0019]
First, a fullerene isolation device 10 according to an embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 1, a fullerene isolation device 10 includes a crystallization tower 12 having a heating unit 11 at an upper portion, and fullerenes as raw materials at an intermediate position in the vertical direction of the crystallization tower 12 (that is, an intermediate portion). The solution supply means 13 for supplying the dissolved solution, the condenser (condenser) 14 for liquefying the vaporized solvent discharged from the top of the crystallization tower 12, and the solvent liquefied by the condenser 14 for the crystallization tower 12 a solvent supply means 15 for supplying the bottom, and a solution extraction means extracting the solution consisting mainly of C ₇₀ from the top of the crystal析塔. These will be described in detail below.
[0020]
The crystallization tower 12 is composed of a vertically long sealed container using a heat-resistant and corrosion-resistant material such as heat-resistant glass and stainless steel, and a cylindrical part 16 constituting an intermediate part and a lower part thereof, and an upper part of the cylindrical part 16. A diameter-enlarged portion 17 serving as a crystallization portion of the specific fullerene having a diameter larger than the cylindrical portion 16 by about 2 to 6 times, for example. The lower portion of the enlarged diameter portion 17 has an inclined surface shape (for example, an inverted truncated cone shape), and the crystallized fullerene falls into the lower cylindrical portion 16 without accumulating on the inclined surface. The cylindrical portion 16 is long enough for the settled fullerene crystals to countercurrently contact the upward flow of the solvent to purify the specific fullerene crystals. Further, the solution inlet from the solution supply unit 13 to good provided in the cylindrical portion 16, may be provided on the boundary between the cylindrical portion 16 and the enlarged diameter portion 17, the lower portion of the enlarged diameter portion 17 May be provided.
The circumference of the enlarged diameter portion 17 constitutes the heating portion 11, and a jacket portion 18 in which a heat medium heated to, for example, 140 ° C. to 170 ° C. circulates is provided. The heat medium supplied to the jacket portion 18 is sent from a known heat medium heating device 18a provided with a circulation pump inside.
[0021]
A stirring blade 19 is provided at the center of the enlarged diameter portion 17, passes through the hemispherical ceiling plate of the enlarged diameter portion 17, and is connected to a rotating shaft 21 that is rotated by a motor 20 at, for example, 100 to 500 rpm. . The rotating shaft 21 and the ceiling plate are sealed so that the internal gas does not leak to the outside. Stirring blade 19, stirring means in the motor 20 and the rotary shaft 21 is formed.
Further, a liquid supply port 22 into which the solution from the solution supply means 13 is placed is provided at the lower part of the enlarged diameter part 17 or the upper part of the cylindrical part 16, and the liquid level sensor 23 is provided at the enlarged diameter part 17. Thus, an open / close electromagnetic valve 25 provided in a pipe line 24 connecting the solution supply means 13 and the liquid supply port 22 is controlled so that a constant level of solution is always stored in the enlarged diameter portion 17. Yes. Reference numeral 26 denotes a control unit of the liquid level sensor 23, and the liquid level sensor 23 and the liquid level sensor control unit 26 constitute a level sensor.
[0022]
The solution supply means 13 is a tank 27 for storing a solution in which fullerenes containing C ₆₀ and C ₇₀ are dissolved in a solvent (for example, ortho-xylene) that is an example of a physical phase that preferentially takes fullerenes other than the specific fullerene. It has a structure in which compressed air (Air) is added from the outside and pushed out to the conduit 24.
A gas discharge port 28 for taking out the solvent gasified by heating by the heating unit 11 is provided at the top of the enlarged diameter portion 17, and the discharged gas is led to the condenser 14 and liquefied. The condenser 14 is provided with a cooling water pipe (not shown) and an exhaust pipe 29 for discharging a gas that is not liquefied to the outside.
[0023]
All or part of the solvent liquefied by the condenser 14 is supplied via a solvent supply means 15 to a room 30 provided at the lower part of the cylindrical portion 16 constituting the crystallization tower 12. The solvent supply means 15 includes a solvent storage tank 31 and a pump 32 that sends the solvent from the storage tank 31, and the solvent supplied to the room 30 becomes an upward flow by the pump 32 and settles from above. It will be in countercurrent contact with the crystal of the specific fullerene.
The storage tank 31 is also provided with an exhaust pipe 33 for discharging the gas stored in the storage tank 31 to the outside.
The room 30 provided in the lower portion of the cylindrical portion 16, which is a specific fullerene to settle from above C ₆₀ containing a large amount of solid (crystal grains), i.e. include specific fullerenes preferentially physical phase (crystalline phase) Precipitate. The precipitated solid is dissolved in a high-purity solvent sent from the storage tank 31, and a part of the solid is discharged out of the system via a liquid distribution pipe 34 which is an example of a specific fullerene extraction means. Fullerene mainly composed of C60 which is concentrated and crystallized by the concentrator is recovered.
[0024]
On the other hand, in the expanded diameter portion 17, the solvent is vaporized by heating, so that the fullerene having low solubility such as C ₆₀ is crystallized and settles downward, and the concentration of fullerene having high solubility such as C ₇₀ becomes high. Therefore, drain pipe 35 is connected with a solution of C ₇₀ mainly a fullerene high solubility to the side of the enlarged diameter portion 17 which is an example of a solution extraction means for discharging out of the system. The solution was taken out by the drainage pipe 35 and can be concentrated and recovered fullerenes containing C ₇₀ in a large amount.
On the other hand, the solid (crystal grains) containing a large amount of C ₆₀ which is crystallized and settles downward in the cylindrical portion 16 is supplied to the chamber 30 while it settles and reaches the lower chamber 30, and is flowed upward by the pump 32. C ₆₀ in the crystal is purified to a sufficient concentration by countercurrent contact with the solvent phase.
Here, the crystal can be purified by adjusting the strength of the pump 32 to adjust the speed of the upward flow and the crystal sedimentation speed.
[0025]
Further, in the embodiment of the present invention, the solution supply means 13 for supplying the raw material is controlled to keep the liquid level of the crystallization tower constant, but the liquid distribution pipe 34 as an example of the specific fullerene extraction means, or The liquid level may be kept constant by controlling the drain pipe 35 which is an example of the solution extraction means, or any one or more of the solution supply means 13, the specific fullerene extraction means, or the solution extraction means It is also possible to continue the continuous operation while keeping the liquid level of the crystallization tower 12 constant in connection with the above means.
In the present embodiment, the specific fullerene crystallized and settled is dissolved in the solvent sent from the storage tank 31 and taken out as a solution. However, it may be settled down and taken out in the form of crystals. The method of the present invention includes the case of taking out in the solid phase by the above method and taking out in the form of a solid-liquid mixed phase.
[0026]
【Example】
Subsequently, the results of the fullerene isolation method using the fullerene isolation device 10 will be described below with reference to FIGS. 1 and 2.
A glass single tube (diameter 8 mm, length 450 mm) provided at the bottom of a jacketed glass separable flask (600 ml, diameter 80 mm) is used as the crystallization tower 12. The separable flask corresponds to the enlarged-diameter portion 17 (concentrated crystallization portion) of the present embodiment, and the glass single tube corresponds to the cylindrical portion 16 and the portion where the crystal at the bottom of the glass single tube settles corresponds to the room 30.
A solution in which 21 g of fullerenes as raw materials are completely dissolved in 2700 g of o-xylene as a solvent has the following composition.
Raw material (1) 21g of mixed fullerene
Oxidized C ₆₀ 1.64 wt%
C ₆₀ 66.62 wt%
Oxide C ₇₀ 0.61wt%
C ₇₀ 26.01 wt%
Higher order fullerene 5.12 wt%
(2) 2700 g of o-xylene
[0027]
The operation procedure is as follows.
(1) Put 600 ml of o-xylene into the crystallization tower 12.
(2) The top of the crystallization tower 12 is stirred by the rotating shaft 21.
(3) The temperature of the top of the crystallization tower 12 is raised to 160 ° C. by a constant temperature bath which is an example of the heating medium superheater 18a.
(4) When the solvent starts to evaporate, the reflux of the vaporized solvent is condensed by the condenser 14 and sent from the storage tank 31 to the room 30 by the pump 32 to be an upward flow is set to 2 ml / min.
(5) When the evaporation temperature further rises and the liquid level in the tower begins to drop, the raw material is supplied from the solution supply means 13 to the crystallization tower 12 in order to maintain the liquid level.
(6) When all the raw materials are put, the temperature of the thermostatic bath is lowered to 150 ° C., and the evaporation rate is lowered. Here, the thermostat temperature is adjusted so that the reflux rate (2 ml / min) and the evaporation rate are equal. Thereby, the state of total reflux can be maintained.
(7) The operation is continued for about 10 hours in the above state.
[0028]
The bottom solution is sampled periodically (at intervals of about 60 minutes), analyzed by HPLC (High Performance Liquid Chromatography), and the time change is followed. Implementation data is shown in FIG.
The numerical implementation data is percentage of C ₆₀ in C ₆₀ + C _70.
As shown in the data, it takes time to concentrate in the actual embodiment, charged raw materials in the practice day (7:00 days 9), after about 5 hours, started observed precipitation of crystals of C ₆₀ is a specific fullerene It was. It seems that it took time until the concentration of ortho-xylene in the crystallization tower was concentrated and C ₆₀ became saturated and precipitation started. At that time, the C ₆₀ concentration at the bottom of the column rose to about 87%. On that day, the experiment was stopped at around 7pm, and the experiment was resumed at 10:00 the next day. The C ₆₀ concentration at the bottom of the tower at the restart was 75%. This seems to be because the C ₆₀ precipitated as crystals because the operation was left as it was also dissolved in the solvent, and the concentration of C ₆₀ returned to the vicinity of the starting point of the operation.
[0029]
On the next day, the operation was performed at a total reflux for about 10 hours. As a result, the C ₆₀ concentration increased from 75% to about 87% in about 1 hour after the start of the operation. This is presumably because the concentration of the solvent had already increased, so when the evaporation of the solvent was started, the precipitation of C ₆₀ crystals started without taking much time. The reason why the C ₆₀ concentration at the bottom of the tower dropped during the process seems to be because the temperature of the thermostatic bath was lowered to 150 ° C. and the evaporation rate was lowered when all the raw materials were added.
The C ₆₀ concentration 10 hours after the start of the next 8 days increased to about 95%.
The bottom fullerene composition after 10 hours of total reflux operation is shown below.
Oxidized C ₆₀ 0.6wt%
C ₆₀ 89.9 wt%
Oxide C ₇₀ 0.0wt%
C ₇₀ 4.4 wt%
Higher order fullerene 5.2wt% (including unspecified substances)
[0030]
As shown in FIG. 2 and the above data, the raw material composition at the start of the implementation had C ₆₀ of 66.6 wt%, but the fullerene composition at the bottom of the tower after the total reflux operation for 10 hours had a C ₆₀ of 89. 9%.
In the above embodiment, not withdrawn specific fullerene bottoms from Haieki tube 34, but the purity of the C ₆₀ in total reflux operation for 10 hours became 89.9%, a specific fullerene bottom of the system The purity of C ₆₀ can be further increased by extracting it to the outside and supplying the raw material with the solution supply means 13 and continuing the continuous operation.
[0031]
As mentioned above, although embodiment of this invention was described, this invention is not limited to this embodiment, The change in the range which does not change the summary of invention is possible.
For example, in the embodiment of the present invention, a crystallization tower having an enlarged diameter is used as the crystallization tower, but the upper part of the crystallization tower is heated to evaporate and remove the solvent. For example, the use of a crystallization tower having a large diameter as a whole without an upper diameter expansion is also included in the scope of the right of the method of the present invention.
[0032]
【The invention's effect】
Isolation device isolation method of fullerene according to claim 6 wherein and claims 7 to claim 9, wherein, were supposed to be able to isolate specific fullerene consisting C ₆₀ from fullerenes in high purity.
In particular, the method according to claim 4 and the apparatus according to claim 9 enable continuous treatment and isolation of specific fullerenes on an industrial scale that does not require enormous energy.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a schematic configuration of a fullerene isolation device according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram of a fullerene isolation method using the same apparatus.
FIG. 3 is an explanatory diagram of the performance of ortho-xylene used as a solvent.
[Explanation of symbols]
10: fullerene isolation device, 11: heating section, 12: crystallization tower, 13: solution supply means, 14: condenser, 15: solvent supply means, 16: cylindrical section, 17: expanded diameter section, 18: jacket Part, 18a: heating medium heating device, 19: stirring blade, 20: motor, 21: rotating shaft, 22: liquid supply port, 23: liquid level sensor, 24: pipe line, 25: open / close solenoid valve, 26: liquid level Sensor control unit, 27: tank, 28: gas outlet: 29: exhaust pipe, 30: room, 31: storage tank, 32: pump, 33: exhaust pipe, 34: liquid distribution pipe, 35: drain pipe

Claims (9)

In isolating the C ₆₀ is a specific fullerene fullerenes, the specific fullerene captured physical phase preferentially, the physical phase incorporating fullerenes other than the specific fullerene preferentially, crystals of the specific fullerene to settle A method for isolating fullerenes, comprising obtaining the specific fullerene having an increased purity by contacting it with an upward flow . The C ₆₀ is a specific fullerene reached by heating the solution of fullerenes saturated solubility from the concentrated solution and the solvent evaporated off to preferentially precipitate, the precipitated said specific fullerene, preferential fullerenes other than the specific fullerene A method for isolating fullerenes, comprising isolating the specific fullerenes by increasing the purity of the specific fullerenes by bringing the solvent to be dissolved in contact with the crystals of the specific fullerenes to be precipitated in an upward flow . The fullerene solution is put into a crystallization tower composed of a vertically long container, and the upper part of the crystallization tower is heated to evaporate and remove the solvent at the upper part of the crystallization tower, so that the specific fullerene C ₆₀ is preferentially precipitated. Then, the solvent removed by evaporation is condensed in a condenser, and a part or all of the solvent is returned to the lower part of the crystallization tower to cause an upward flow in the crystallization tower. crystal phase and the solvent phase is contacted, the isolation method of fullerenes and isolating by increasing the purity of the specific fullerene of the crystalline phase by generating. In the isolation method of fullerene according to claim 3, supplies the solution continuously fullerenes than the middle portion of the crystal析塔, and characterized by taking out the solution of the specific fullerene from the bottom of該晶析塔To isolate fullerene. In the isolation method of a fullerene according to any one of claims 3 and 4, fullerenes put the crystal析塔is composed mainly of C ₆₀ and C _70, are the specific fullerene from the bottom of the crystal析塔A method for isolating fullerene, comprising extracting a solution mainly comprising C ₆₀ and a solution mainly comprising C ₇₀ from the upper part of the crystallization tower.   The fullerene isolation method according to any one of claims 2 to 5, wherein the solvent is an aromatic hydrocarbon. An apparatus for isolating a specific fullerene from a solution of fullerenes in which fullerenes having different molecular weights are dissolved,
In the upper part, a crystallization tower comprising a vertically long container having a heating part for heating the solution and evaporating the solvent,
Solution supply means for supplying the solution as a raw material to an intermediate part of the crystallization tower;
A condenser for extracting and liquefying the vaporized solvent discharged from the top of the crystallization tower;
Solvent supply means for supplying the solvent liquefied by the condenser to the lower part of the crystallization tower;
A specific fullerene extraction means for extracting a specific fullerene having low solubility from the lower part of the crystallization tower;
Isolation device fullerene characterized by having a solution withdrawal means withdrawing a solution consisting mainly of C ₇₀ from the top of the crystal析塔.   8. The fullerene isolation apparatus according to claim 7, wherein the crystallization tower has a crystallization portion of the specific fullerene at an upper portion thereof and a cylindrical portion having a length sufficient to purify crystals that settle below the crystallization tower. A fullerene isolation device characterized by comprising:   The fullerene isolation device according to any one of claims 7 and 8, wherein a stirring means for stirring the introduced solution is provided at an upper portion of the crystallization tower, and A level sensor for controlling the upper liquid level is provided, and the liquid level control is performed in connection with one or more of the solution supply means, the specific fullerene extraction means, and the solution extraction means. Fullerene isolation device characterized by the above.

Images