JPH09227111A - Apparatus for separating and purifying fullerene and separation and purification - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide both an apparatus for separating and purifying fullerene capable of separating and purifying the high-purity fullerene at a low cost without using any organic solvent at all and a method for separating and purifying the fullerene. SOLUTION: This apparatus for separating and purifying fullerene is equipped with at least a heating vessel 3 for heating the fullerene and subliming the fullerene, a trap 4, connected to the heating vessel 3 and used for depositing the sublimed fullerene and a vacuum device for decompressing and sucking the interiors of the heating vessel 3 and the trap 4. The heating vessel 3, trap 4 and vacuum device are arranged in the order. The trap 4 is preferably divided into two or more sections. The method for separating and purifying the fullerene comprises setting the temperature of the trap 4 on the side of the heating vessel 3 at a higher one than that on the side of the vacuum device.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an apparatus and method for separating and purifying fullerenes.

[0002]

BACKGROUND OF THE INVENTION Fullerenes have recently been discovered as a third carbon solid molecule after graphite and diamond, and are allotropic forms of carbon having a spherical shell structure. Fullerene C _{60 with} 60 carbons representing fullerene
Has a regular pentagonal structure of 12 like a soccer ball.
A hexahedron is a 20-sided 32-sided hexahedron. As fullerene, C ₆₀ , C ₇₀ fullerene C ₇₀ , C 8 fullerene
4 fullerene C ₈₄ is mainly present, and other than this, carbon number 1
C ₇₆ , C ₇₈ , C ₈₂ , C ₉₀ as fullerene of 00 or less,
It is known that all of C ₉₄ and the like have a cage structure with a unique shape, but the amount is extremely smaller than that of C _60, and the existence of macromolecule fullerenes with more than 120 carbon atoms has been confirmed. ing.

Such fullerenes are useful in the following points. (1) Utilization of fullerene as a derivative by chemical modification: C ₆₀ has various highly reactive electrons surrounding the outside of a spherical molecule and easily reacts with other substances to synthesize various derivatives. Attempts have been made to create substances with new functions. For example, we are in the process of developing a new functional plastic by introducing fullerene into a part of the polymer or using it as a catalyst. Focusing on the property that the complex of C ₆₀ and metal occludes hydrogen, the acetylene compound Has been successfully hydrogenated to a propylene compound. Further, by filling C ₆₀ or C ₇₀ in the holes of a porous material called zeolite, alcohols and the like can be efficiently synthesized. Furthermore, the hydrogenation effect of heptane in the fullerene-supported palladium catalyst is several times that of activated carbon. (2) Application to medicine: In order to modify that C ₆₀ is only soluble in organic solvents such as benzene, it has water solubility by making a derivative in which a water-friendly substituent such as alcohol is added to fullerene. I am making it. It has been discovered that these derivatives have the property of inhibiting the activity of proteolytic enzymes, which are essential for the expression of HIV, which is the cause of AIDS, and the property of cleaving a specific site of DNA, which is the main body of a gene, when irradiated with light.

(3) Use as a nonlinear optical functional material:
An electron transfer complex formed by a compound containing a fullerene and an electron donor exhibits a third-order nonlinear optical effect. (4) Use as a metal-encapsulated fullerene: C ₆₀ crystals show semiconductivity, but when an alkali metal or the like is added, they become metal or show superconductivity. It also becomes a ferromagnetic material when mixed with an organic amine-based substance. (5) Other uses: A photoelectric conversion element in which a special organic thin film was laminated on a C ₇₀ thin film was prototyped, and an electrophotographic photosensitive drum of a size that could be mounted on a small commercial copying machine was manufactured. Achieves sensitivity, 20 per minute on A4 paper
It is known that image samples can be obtained at sheet speed. In addition, according to an in vitro test of the effect of C ₆₀ on rat and mouse cells, when C ₆₀ was added to undifferentiated cells before becoming limbs, chondrocytes increased four times as much as usual, It is expected that if artificial bone made of plastic or metal is coated with C ₆₀ , cartilage will grow and biocompatibility will increase. Further, it is also used as a diamond synthetic material under normal temperature and high pressure. In this way, fullerenes are useful as new materials, medicines, etc. because they are related to various fields of use.

Next, a conventional method for producing fullerenes will be described. At the time of discovery, the method for producing fullerenes recognized that the fullerenes were present by synthesizing graphite by evaporating graphite by heating with a laser and introducing an inert gas such as He or Ar into this atmosphere. However, this method is not suitable for producing a large amount of soot, and arc discharge is now mostly used. An example of its manufacturing method is
Using a DC power source of 50 to 100 A, 20 to 40 V (20 kW), using a carbon rod (weight: 4.6 g) having a diameter of 5 to 6 mm and a length of 1000 to 200 mm as an anode and a carbon rod as a cathode, a He atmosphere ( The carbon rod of the anode is vaporized by the arc discharge at 100 to 400 Torr), and soot is generated. The soot generally contains 5 to 10% by weight of fullerenes. And what separated fullerene from this soot is called coarse fullerene.

Further, there is disclosed a method for synthesizing fullerene from soot vaporized at 2700 ° C. by heating a graphite rod in a He atmosphere with high frequency, or a method for synthesizing fullerene by utilizing plasma discharge. Have been tried. Among these, the highest production yield of 40% by plasma discharge is reported in the literature.

[0007]

[Problems to be Solved by the Invention] Reduction of fullerene production cost is an important factor for increasing the competitiveness of fullerene-based products, and although the price has been decreasing year by year, fullerene is still as high as precious metals. There is a problem.

[0008] There are still many unclear points about the fullerene production mechanism, and it has not been successful to selectively produce C ₆₀ , C _{70 and the} like. Therefore, including various fullerenes such as C _60, C _70, from the crude fullerene such as the aforementioned soot, it is desirable to separate and purify fullerenes such as C _60, C ₇₀ at a high concentration, respectively. Which fullerene is needed among the many types of fullerenes, since a large-scale production method of fullerenes has just been discovered, or because clear uses have not been fully established? Not clear. However, since unknown properties are expected for fullerenes in the future, from crude fullerenes,
It is preferable to separate and purify specific fullerenes such as C ₆₀ and C ₇₀ .

Initially, many researchers conducted mass spectrometry (M
Although much effort has been put into the confirmation and identification of fullerenes by S), it is almost impossible to study the fullerene-related fields only by confirmation by mass spectrometry. For the study of physical properties typified by superconductivity, the study of catalytic action in chemical reactions, the study of chemical properties, and the measurement of biological activity, fullerene with a constant number of carbon atoms can be obtained in a stable amount from fullerenes with various structures. It is essential to do this. In order to realize this, a method for separating and purifying a specific fullerene from carbon soot is required.

As this separation and purification method, a separation technique called liquid chromatography (LC) is known. This separation technology uses fullerene with several organic solvents (benzene,
Toluene, hexane, carbon disulfide, etc.) is a method that utilizes the fact that the solubility is not so great but it is soluble. For liquid chromatography, a separation method called free-flow chromatography called column chromatography is used.
There is a method of achieving high resolution separation by pumping the moving bed liquid with a high performance pump called (high performance pump liquid chromatograph). In the fractionation by column chromatography, when the fractionated amount increases, the amount of the solvent used increases, so that it takes a lot of time to prepare, recover, and manage the organic solvent, which is a major factor of high cost. Further, since resolution is low, not effective for various Higher fullerene C _{74 <separation} and purification of more than C _74.

On the other hand, in the separation and purification by the HPLC method, if a column of silica gel with various chemical modifications such as an octadecylsilane (ODS) column which is a chemically-bonded silica and a mobile phase are selected, the fullerene content is determined. Take
It can be separated and purified, and is an indispensable separation means for separation of higher fullerenes. However, it is not easy to efficiently separate and purify a large amount of crude fullerenes such as crude fullerenes at one time, and there is a problem that a multi-step chemical operation is required until a constant amount of fullerenes is recovered.

On the other hand, a method of selectively separating and purifying only C ₆₀ by flash chromatography using activated carbon was developed in the United States in 1992. According to this method, the amount of the solvent is 1/20 or less of the conventional amount, and the separation and purification time is also 1/5 to 1/30 or less, which is a great labor saving compared with the separation and purification method by the HPLC method. It can be said that this is one of the best methods if only the separation of C ₆₀ is targeted, but it has a drawback that it cannot be applied to the separation other than C ₆₀ because the adsorption power of fullerene on activated carbon is extremely large.

Separation and purification of fullerenes by liquid chromatography has been put into practical use as a large-scale processing method, but the problem is that it is not desirable in terms of environment and economy to use a large amount of moving-bed solvent. Further, it has been revealed that fullerene is very active, and there is a problem that pure fullerene is difficult to obtain because the fullerene purified by precipitation from the solvent in the growth of a single crystal is affected by the solvent.

As described above, the development of a method for separating and purifying fullerenes without using an organic solvent is very meaningful. As one of the methods for separating and purifying fullerenes, Applied Physics Letter (Appl. Phys. Lett.
Vol. 65, no. 3,18 Jul 1994)
However, this method is a separation method by molecular distillation using the Knuzen principle, and the apparatus is complicated, and is not suitable for efficient large-scale processing.

The present invention has been made in view of the above circumstances, and is an apparatus for separating and refining fullerene of extremely high purity at a low cost, which is dangerous or toxic and does not use a large amount of organic solvent at all. And providing a separation and purification method.

[0016]

The invention according to claim 1 is to provide a heating container for heating and sublimating fullerene contained in the fullerene-containing soot or the crude fullerene, and the fullerene sublimated by being connected to the heating container. At least a trap for precipitating the heating container and a vacuum device for evacuating the inside of the heating container and the trap, and the heating container, the trap, and the vacuum device are arranged in this order. It is a separation and purification device for fullerenes.

According to a second aspect of the present invention, the heating container and the trap are housed in a tubular container having one end sealed and an opening at the other end, and the opening is connected to a vacuum device. The fullerene separation / purification device according to claim 1.

According to the third aspect of the present invention, there is provided temperature control means for forming a temperature gradient in the trap so that the temperature of the heating container of the trap becomes high and the temperature of the trap becomes low toward the vacuum device. The fullerene separation and purification device described.

The invention according to claim 4 is characterized in that the trap is composed of two or more separable compartments so that the fullerene precipitate deposited in the trap can be divided into two or more and taken out. The fullerene separation and purification device according to any one of claims 1 to 3.

The invention according to claim 5 is characterized in that the heating container and the trap are made of a heat-resistant material such as quartz glass, ceramics or stainless steel, and the fullerene according to any one of claims 1 to 4 is characterized. It is a separation and purification device.

The invention according to claim 6 is characterized in that a fibrous packing layer is arranged at a connection portion between the heating container and the trap, and separation and purification of fullerene according to any one of claims 1 to 5 is characterized. It is a device.

In a seventh aspect of the present invention, the fullerene-containing soot or the fullerene contained in the crude fullerene is heated in a vacuum atmosphere to be sublimated, and a temperature gradient is applied to the sublimated fullerene to lower its temperature along the moving direction thereof. It is a method of separating and purifying fullerenes, which is characterized in that the fullerene is guided to and deposited in a trap.

The invention according to claim 8 is the method for separating and purifying fullerene according to claim 7, characterized in that the vacuum atmosphere has a degree of vacuum of 1 Torr to 1 × 10 ⁻³ Torr.

The invention according to claim 9 is characterized in that the temperature gradient of the trap is set so that one end side thereof is set to 500 to 650 ° C and the other end side thereof is set to 200 to 300 ° C. The method for separating and purifying fullerenes according to claim 7 or 8.

[0025]

1 is a cross-sectional view of an embodiment of a fullerene separation / purification device of the present invention. The apparatus for separating and purifying fullerene of the present invention is for heating the sublimation contained in the fullerene-containing soot 10a or the crude fullerene 10b to sublimate it, and to deposit the sublimated fullerene connected to the heating vessel 3. And at least a vacuum device for evacuating the inside of the heating container 3 and the trap 4, and the heating container 3, the trap 4, and the vacuum device are arranged in series in this order. is there. And in the example shown in FIG.
The heating container 3 and the trap 4 are housed in a tubular container 2 which is sealed at one end and has an opening at the other end.

The container 2 is a pressure-resistant container for accommodating the heating container 3 and the trap trap 4 therein, and evacuating the inside of the heating container 3 and the trap trap 4 to heat them. The container 2 is sealed at one end, and the opening at the other end is connected to the vacuum device side. If the heating container 3 and the trap 4 are housed inside the container 2, it is not necessary to connect the heating container 3 and the trap 4 so that vacuum leakage does not occur.
It is easy to make a vacuum inside these. Further, when the heating container 3 and the trap 4 are housed side by side in the container 2, the separation and purification device can be downsized. A preferable shape of the container 2 is a tubular body having one end sealed, and an example of the size thereof is a tube length of 0.5 to 1 m and an outer diameter of 5 to 25 mm. The container 2 preferably withstands a temperature of 1000 ° C,
Above all, it is preferably composed of a heat resistant material such as quartz, ceramics, and stainless steel.

The heating container 3 accommodates a fullerene-containing soot 10a or a fullerene-purifying material such as a crude fullerene 10b therein, as well as the fullerene-containing soot 10a.
Alternatively, it is a container for heating and sublimating the fullerene contained in the crude fullerene 10b. The heating container 3 has one end sealed, and the other end has an opening for connecting to the trap 4. The heating container 3 is externally heated by the heating means such as the electric furnace 5a via the container 2 and the like. The heating container 3 is preferably made of a heat resistant material such as quartz, Pyrex or stainless steel.

The trap 4 is a container connected to the heating container 3 for condensing and depositing the sublimated and vaporized fullerene on the inner wall surface thereof. And trap 4
Is preferably a tubular body and has openings at both ends.

The trap 4 is externally heated by a heating means such as an electric furnace 5b in order to efficiently separate and purify the fullerene. The temperature of the trap 4 is controlled by a heating means having a known temperature control means as described later. The temperature of the trap 4 is preferably controlled by a temperature control means capable of forming a temperature gradient in the trap 4 in which the temperature decreases from the heating container 3 side of the trap 4 toward the vacuum device side. The trap 4 is made of a heat resistant material such as quartz, Pyrex or stainless steel.

Although the trap 4 can be made the same body as the heating container 3, it is preferable that the trap 4 is made a separate body from the heating container 3. If it is provided as a separate body, it is easy to take out the fullerene precipitate from the trap 4. If the trap 4 is separated and is composed of two or more separable compartments, the fullerene precipitate can be collected in two or more. Accordingly, C _{70 <,} a C _{7 0,} C product content different fullerenes such as ₆₀ can be easily collected.

The trap 4 is preferably divided into 2-8 pieces. In the example shown in FIG. 1, the trap 4 is composed of five compartments, each of which is composed of five tubular bodies divided into equal lengths. All the compartments of the trap 4 have openings at both ends. When the trap 4 is divided into a plurality of compartments in this way, a plurality of purified products having different fullerene contents such as C ₆₀ and C ₇₀ can be obtained by a single separation and purification operation.

The vacuum device is a device for evacuating the inside of the container 2, the heating container 3, and the trap 4 to a vacuum, such as a vacuum pump.

Further, it is preferable to dispose the fibrous filling layer 6 at the connecting portion between the heating container 3 and the trap 4. The fibrous filling layer 6 is obtained by storing the fullerene-containing soot 10a or the crude fullerene 10b in the heating container 3 and then heating the heating container 3
It is necessary to prevent the soot or the coarse fullerene, which are fine powders, from scattering when the inside is made a vacuum atmosphere. As the fibrous material, a cotton-like material that can withstand a temperature of 1000 ° C. is preferable, and among them, ceramic wool, quartz glass wool, etc. having excellent heat resistance are preferable.

When the heating container 3, the trap 4, and the vacuum device are arranged in this order, the fullerene vaporized in the heating container 3 which is located on the sealing side of the container 2 and is accommodated in the heating device 3 is removed from the vacuum device. It flows and moves in only one direction. Then, the vaporized fullerenes that have flowed into the trap 4 are, for example, on the inner wall surface of the temperature-controlled trap 4,
Various fullerenes are trapped (captured) at different deposition positions according to the vapor pressure of fullerenes. That is, the fullerenes are trapped from the heating container 3 side (upstream side of the flow) of the trap 4 in the order of the carbon number of the fullerene, for example, the order of fullerene having more than 70 carbon atoms (C _{70 <} ), C ₇₀ , and C _60. 4 is deposited at different positions toward the vacuum device side (downstream side of the flow), so that a purified product containing a specific fullerene in a high concentration can be obtained.

The method for separating and purifying fullerenes of the present invention is
The fullerene contained in the fullerene-containing soot 10a or the crude fullerene 10b is heated in a vacuum atmosphere to be sublimated, and the sublimed fullerene is introduced into a trap 4 having a temperature gradient that decreases in temperature along the moving direction thereof, This is a separation and purification method in which sublimated fullerenes are deposited in the trap 4.

When the separation and purification apparatus shown in FIG. 1 is used,
The method for separating and purifying fullerenes will be described in more detail below. Fullerenes sublime when heated under vacuum. Therefore, the inside of the heating container 3 and the trap 4 is made to have a vacuum degree of 1 Torr to 10 ⁻³ Torr by a vacuum device so that the fullerene is easily sublimated.

Further, the fullerene contained in the fullerene-containing soot 10a or the crude fullerene 10b is the electric furnace 5.
a through 400, via the container 2, the heating container 3, etc.
Sublimates when heated to 1000 ° C. If it is less than 400 ° C, the sublimation rate is slow, and if it exceeds 1000 ° C, the sublimation rate of fullerenes becomes too high, and coarse fullerenes are easily mixed in the precipitate. The heating container 3 is not only heated at a constant temperature within the above-mentioned temperature range, but is rapidly sublimated from around 400 ° C at which fullerene sublimation begins to occur at 1000 ° C.
It is preferable to heat gradually. Therefore, the electric furnace 5
It is preferable that b is program temperature controlled in this way. 2 is a graph showing an example of the temperature distribution of the heating container 3, and shows the distance l (shown in FIG. 1) from the left end of the heating container 3 (the sealing portion of the heating container 3) and the temperature at that position. It is the graph shown.

The fullerene vaporized in the heating container 3 passes through the fibrous packing layer 6 and is introduced into the trap 4 through the opening of the compartment on the left side of the trap 4. Then, it is condensed and deposited under a vacuum atmosphere on the inner wall surface of the trap 4 whose temperature is controlled to be lower than that of the heating container 3. In order to improve the degree of separation and purification of fullerene, it is preferable that the trap 4 be provided with a temperature gradient in which the temperature decreases along the moving direction of the sublimated fullerene. That is, it is preferable that the trap 4 be provided with a temperature gradient such that the heating container 3 side is heated to a higher temperature and the vacuum device side is cooled to a lower temperature. It is desirable to make a difference. By providing such a temperature gradient, it is easy to deposit fullerenes in order according to the number of carbon atoms, and it is easy to obtain high-purity fullerenes.

Therefore, one end of the trap 4 (heating container 3
The temperature of the trap 4 is set to 500 to 650 ° C, the temperature of the other end (vacuum pump side) is set to 200 to 300 ° C, and a temperature gradient is provided in the trap 4. When the vaporized fullerene is circulated in the trough 4 having such a temperature gradient, C
_{It is} easy to adjust the deposition position of fullerenes such as ₆₀ and C _{70 in} the trap. Therefore, the purification efficiency of fullerene is excellent. B in FIG. 2 is a graph showing an example of the temperature gradient of the trap 4, and is a graph showing the distance 1 from the left end of the heating container 3 (the sealing portion of the heating container 3) and the temperature at that position. In the example shown in b in FIG. 2, the temperature at the left end (heating container 3 side) of the trap 4 is about 505 ° C. and the temperature at its right end (vacuum pump side) is about 200 ° C. The trap 4 is provided with a temperature gradient in which the temperature gradually decreases from the side toward the vacuum pump.

[0040]

Hereinafter, the present invention will be described in detail. In the following Examples and Comparative Examples, the amounts,% and ratios all mean weight,% by weight and weight ratio. First, the relationship between the heating temperature of the fullerene-containing soot 10a and the amount of sublimation of fullerene was examined using the separation and purification apparatus shown in FIG. 3 g of the fullerene-containing soot 10a containing 7.3 wt% of fullerene was placed in the tubular heating container 3, and the opening of the heating container 3 was filled with ceramic wool to arrange the packing layer 6. The heating container 3 was housed inside the tubular pressure-resistant container 2 with one end sealed.

For the trap, five separated tubular bodies of equal length and having openings at both ends were prepared. The five tubular bodies were brought into close contact with each other to form a trap having compartments separable from the four dividing portions. The trap was inserted into the tubular container 2 and brought into close contact with the filling layer 6, whereby the trap 4 and the heating container 3 were connected via the filling layer 6.

Next, the inside of the container 2 was evacuated by a vacuum pump to adjust the degree of vacuum of the atmosphere of the heating container 3 and the trap 4 to 3 × 10 ⁻² torr. In this vacuum atmosphere,
The temperature of several points was changed in the temperature range of 500 to 900 ° C., and the fullerene-containing soot 10a was heated for 3 hours at each temperature. The fullerene sublimated in the heating vessel 3 passed through the packed bed 6 and was introduced into the trap 4, where it was condensed and deposited on the inner wall surface thereof. After 3 hours, the trap 4 was taken out of the container 2, all the deposits deposited in the trap 4 were collected, and the total weight thereof was measured. The temperature of the left end (heating container 3 side) of the trap 4 was 550 ° C, and the temperature of its right end (vacuum pump side) was 300 ° C. The relationship between the heating temperature of the fullerene-containing soot 10a and the total weight of fullerenes deposited in the trap 4 is shown in FIG.

As can be seen from FIG. 3, fullerene-containing soot 1
When the heating temperature of 0a was 500 ° C., the amount of precipitated fullerenes was 0.003 g. The amount of precipitation increased as the temperature increased, and 0.22 g of fullerene was precipitated at 900 ° C. This indicates that almost 100% of the fullerene was sublimated from 3 g of the fullerene-containing soot and deposited in the trap 4. That is, in order to efficiently sublime the fullerene contained in the fullerene-containing soot 10a, it was found that the fullerene-containing soot 10a should be heated to 500 to 900 ° C.

Example 1 Next, 50 mg of crude fullerene 10b was used to separate and purify fullerenes by the separation and purification apparatus shown in FIG. The weight ratio (C ₆₀ / C ₇₀ ) of C ₆₀ and C ₇₀ of this crude fullerene 10b was 5. 50 mg of crude fullerene 10b is placed in the heating container 3 and charged with an electric furnace 5a.
Heated to 0 ° C.

The temperature of each compartment of the trap 4 divided into six compartments (however, the temperature at the center of the compartment) is from the compartment on the left side (compartment on the heating container 3 side) to the compartment on the right side (vacuum pump side). Toward 550 ° C, 510 ° C, 450 ° C,
The temperatures were 415 ° C, 380 ° C, and 310 ° C. The interior of the container 2 is evacuated by a vacuum pump to sublimate the fullerene in the heating container 3 in a vacuum atmosphere, and the sublimated fullerene is guided into the trap 4 to be precipitated, thereby separating and purifying the fullerene in the same manner as described above. I went. Then, after the purification was completed, the trap 4 was taken out from the container 2, the trap 4 was separated from the dividing line of the trap 4 to be separated into 6 pieces, and the precipitate was taken out from each compartment to obtain a 6-divided fullerene precipitate. . FIG. 4 is a section (zone) of the trap 4.
2 is a graph showing the relationship between the temperature and the weight ratio of C ₆₀ and C ₇₀ (C ₆₀ / C ₇₀ ) in the precipitate taken out from the compartment.

The C ₆₀ / C ₇₀ of the precipitate taken out from the 550 ° C. compartment was 3.5, and the C of the precipitate in the 510 ° C. compartment was C.
₆₀ / C ₇₀ was 1.06, and the C ₆₀ / C ₇₀ of the precipitate in the 310 ° C. section on the vacuum apparatus side reached 275, and the purity of C ₆₀ was 99.6 wt%. That is, considering that the C ₆₀ / C ₇₀ of the crude fullerene before purification was 5, 310
It can be seen that the precipitate in the ° C compartment is a highly purified C ₆₀ . The C ₆₀ / C _{70 of} what remained in the heating container 3 after the purification was 2.7, which was C _{60 of} the crude fullerene.
It was also revealed that the ratio of / C ₇₀ was significantly changed from 5 to 2.7. FIG. 5 is a diagram showing yields of deposits in each section. In addition, the yield of fullerene means the weight of fullerene deposited in each compartment, and the fullerene sample 1 used.
It is a value obtained by dividing the amount of 0b by 50 mg and multiplying by 100.

—Example 2— Using the separation and purification apparatus of the present invention shown in FIG. 1, 200 mg of fullerene-containing soot 10a was used to separate and purify fullerenes under the following separation and purification conditions. As the soot 10a,
Use in and the proportion of C ₆₀ includes 7% strength fullerene (14 mg strength) is 83%, in C ₇₀ 14%, what is remaining 3% of higher than C ₇₀ fullerene (C _{70 <)} I was there.

The degree of vacuum in the tubular container 2 is 0.03.
And the heating temperature of soot 10a is kept constant at 640 ° C,
The temperature of each section of the trap 4 (separated into 5 sections) (the temperature at the center of the section) goes from the section on the left side (the heating container 3 side) of the trap 4 to the section on the right side (vacuum pump side). 505 ° C, 440 ° C, 395 ° C, 36
The temperature was 0 ° C and 300 ° C, and the separation and purification time was 21 hours. After completion of the separation and purification, the trap 4 is taken out from the container 2, the trap 4 is separated from the partition line into five pieces, and the precipitates are collected from each of the separated compartments, whereby precipitates at different deposition positions are collected. I got 5 kinds. The composition analysis of fullerene C ₆₀ , C ₇₀ , and C _{70 <} in each of these precipitates was performed using a high-performance pump liquid chromatograph (HPLC), and the separation and purification effect was investigated.

FIG. 6 shows the temperature of the compartments and C in the deposits of each compartment.
₆ is a graph showing the content rates of ₆₀ , C ₇₀ and C _{70 <} in weight percent. As shown in FIG. 6, the content rate of C ₆₀ is 3
It is 83 to 95% by weight in the case of deposits at a temperature of 95 ° C or lower, and 20% in the case of deposits in a temperature of 450 ° C or higher.
It was below. On the other hand, the concentration of C ₇₀ is 300 ° C, 39
14-16% for precipitates in 5 ° C and 505 ° C compartments
However, it can be seen that the 440 ° C. compartment was separated and purified to a very high purity of 70%. In other words, C ₆₀ is 395
Precipitates collected from the zone below ° C contained in high purity, and 70% of C ₇₀ was contained in the precipitate collected from the zone at 440 ° C.

As shown in FIG. 6, the presence of C _{70 <} was not observed in the deposits collected from the 300 compartments, and in the precipitates collected from the 360 ° C to 505 ° C compartments. The precipitates that were found to exist in Example 1 and were collected from the section with a higher temperature had a higher C _{70 <} content. 50
C _{70 <} 6 in the precipitate collected from the 5 ° C compartment.
0% was included.

As described above, the compartment of the trap 4 allows the C ₆₀ and C ₇₀ in the precipitate collected from the compartment.
And C _{70 <} concentrations (ratio) are significantly different, and C _{70 <} ,
It was found that C ₇₀ and C ₆₀ were separated and purified according to the sections from the high temperature side to the low temperature side. In other words, it was possible to obtain the ones in which the fullerenes of C _{70 <} , C ₇₀ , and C ₆₀ were contained in extremely high purity by a single separation and purification operation. The weight of the deposit in each section is shown in FIG.

According to FIG. 7, the amount of fullerene deposited (trap amount) collected from the 300 ° C. compartment was 1.5 mg,
The amount of precipitation in the section of 360 ° C was 3.9 mg, the amount of precipitation in the section of 395 ° C was 6.9 mg, the amount of precipitation in the section of 440 ° C was 1.0 mg, and the amount of precipitation in the section of 505 ° C was 0. 9 mg
Met. At around 400 ° C, 49% occupies half of the total amount of the precipitate, and at the same time, the total weight of precipitation at 400 ° C or lower is 87%, and the amount of precipitation at 400 ° C or higher remains 1%.
At 3%, it can be roughly seen that the ratio of the fullerene C ₆₀ contained in the crude fullerene is close to 83% and the ratio of C ₇₀ to 14%.

The total amount of these precipitates is 14.2 m.
It was g, which means that the amount of fullerene in 200 mg of crude fullerene (14 mg or more) sublimated almost 100% and was precipitated and trapped. The fullerene content in the soot obtained by solvent extraction is 7% by weight, which is a sufficient separation and purification rate.

[0054]

INDUSTRIAL APPLICABILITY As described above, the separation / purification apparatus and separation / purification method for fullerenes of the present invention are separation / purification apparatus and separation / purification method that do not use a large amount of organic solvent at all because they are all performed in a dry process. Therefore, the cost for separating and purifying fullerenes can be reduced, and the work can be performed safely and efficiently without danger. Furthermore, it is a separation / purification device and a separation / purification method capable of obtaining several kinds of purified products containing a fullerene having a constant carbon number in an extremely high purity by a single separation / purification operation. Further, since the trap is divided into two or more compartments, it is possible to easily separate the precipitate containing the fullerenes having different carbon numbers.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a fullerene separation / purification device according to an embodiment of the present invention.

FIG. 2A is an example of a temperature gradient of a heating container, and FIG.
3 is a graph showing an example of the temperature gradient of the trap.

FIG. 3 is a graph showing the relationship between the heating temperature of crude fullerenes and the sublimation amount of fullerenes.

FIG. 4 Temperature of trap compartments and C of deposits in each compartment
Is a graph showing the weight ratio of ₆₀ and C _70.

FIG. 5 is a graph showing the relationship between the temperature of the trap compartment and the fullerene yield in each compartment.

6 is a graph showing the relationship between the temperature and the C _60, the proportion of C ₇₀ and higher fullerenes C ₇₀ than C _{70 <precipitate} in each Lot trap.

FIG. 7 is a graph showing the temperature of the compartment of the trap and the weight of the deposit in each compartment.

[Explanation of symbols]

2 ·· Container, 3 · · Heating container, 4 · · Trap, 5a,
5b .. Electric furnace, 6 .. Fibrous packed bed, 10a .. Fullerene-containing soot, 10b .. Coarse fullerene

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Ryuichi Ogawa 4-320 Tsukagoshi, Sachi-ku, Kawasaki-shi, Kanagawa Nihon Oxygen Co., Ltd. Within the corporation

Claims (9)

[Claims] 1. A heating container for heating and sublimating fullerene contained in fullerene-containing soot or crude fullerene, a trap connected to the heating container for depositing sublimated fullerene, and the heating container and trap. And a vacuum device for evacuating the inside of the fullerene, and a heating container, a trap, and a vacuum device are arranged in this order. 2. The heating container and the trap are housed in a tubular container having one end sealed and an opening at the other end, and the opening is connected to a vacuum device. The fullerene separation and purification device described. 3. The apparatus for separating and purifying fullerenes according to claim 1 or 2, further comprising temperature control means for increasing the temperature of the heating container side of the trap and forming a temperature gradient in the trap toward the vacuum device side. . 4. A fullerene precipitate deposited in the trap can be divided into two or more and taken out by a trap.
The separation / purification device for fullerenes according to any one of claims 1 to 3, wherein the separation / purification device is composed of the above separable compartments. 5. The heating container and the trap are made of quartz glass,
The fullerene separation and purification apparatus according to any one of claims 1 to 4, which is made of a heat-resistant material such as ceramics or stainless steel. 6. A fibrous filling layer is arranged at a connecting portion between the heating container and the trap.
An apparatus for separating and purifying fullerene according to any one of 1. 7. Fullerene contained in fullerene-containing soot or crude fullerene is heated in a vacuum atmosphere to be sublimated, and the sublimated fullerene is introduced into a trap having a temperature gradient that decreases in temperature along its moving direction. A method for separating and purifying fullerenes, which comprises depositing. 8. The method for separating and purifying fullerenes according to claim 7, wherein the vacuum atmosphere has a degree of vacuum of 1 Torr to 1 × 10 ⁻³ Torr. 9. The trap temperature gradient is 5 at one end side.
8. The temperature is set to 00 to 650 [deg.] C., and the other end side is set to 200 to 300 [deg.] C.
Alternatively, the method for separating and purifying fullerene according to item 8.