JPH052012A - Carrier for gas chromatography using aggregate of carbon fine particles and method for producing the same - Google Patents

Abstract

(57) [Summary] [Structure] An ultrafine particle material selected from carbon black having a specific particle diameter and free carbon is attached to the surface of a fine particle material selected from among non-melting thermosetting resins. After that, a liquid thermosetting resin that can be carbonized by heating and an organic solvent are added to form a slurry, which is dried, molded, cured, calcined and carbonized, and then pulverized and classified to have a bulk specific gravity of 0.2 to 0.5, a carrier for gas chromatography using a carbon fine particle aggregate having a specific surface area of 1.0 m ² / g or less by a nitrogen gas adsorption method and having a plurality of protrusions having a height of 1 μm to 20 nm on the surface. [Effect] The adsorption power is equal to or higher than that of diatomaceous earth type, and a wide range of analysis including analysis of an aqueous solution of a high boiling point component is possible, and the liquid phase carrying ability is good, and the wettability of all liquid phases is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is capable of performing a wide range of analyzes including analysis of aqueous solutions of high-boiling components, and particularly gas chromatography using a carbon fine particle aggregate having excellent wettability with a liquid phase and having a large liquid phase carrying ability. And a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, as a carrier for gas chromatography (hereinafter referred to as a carrier for gas chromatography), a carrier obtained by sintering natural diatomaceous earth and treating it with an acid and a silanizing agent has been widely used. This is because diatomaceous earth has a large liquid phase supporting force and a small adsorbing force.

However, in this type of carrier for gas chromatography, since diatomaceous earth is a natural product, there is a large variation between lots, and since it is easily hydrolyzed by water, new adsorption points are developed and the performance is significantly reduced. Therefore, there is a defect that the material containing water cannot be analyzed.

Therefore, the present inventors previously found that the sample containing water, which has a lower adsorptivity than that of diatomaceous earth and has a separation performance equal to or higher than that of diatomaceous earth, has a small variation, and is not hydrolyzed. As a carrier for gas chromatography, which has features such as being able to perform good analysis of "a fine particle of carbon or a thermosetting resin as a base material, a bulk specific gravity of 0.2 to 0.5 and a specific surface area of 1 m ² / g or less. A carrier composed of an adjusted carbon fine particle aggregate "was proposed (Japanese Patent Application No. 2-7684).

[0005]

However, the carrier composed of the aggregate of carbon fine particles has the performance superior to that of diatomaceous earth as described above, but at the same time, the supporting ability of the liquid phase used for the analysis is not sufficient. Further, there is a defect that the wettability with a part of liquid phase such as polyester liquid phase is insufficient. Therefore, development of a carrier for gas chromatography that is used for all purposes has been desired. An object of the present invention is to solve the above-mentioned drawbacks and to provide a carrier for gas chromatography which has a good supporting ability for a liquid phase used for analysis and has improved wettability of all liquid phases.

[0006]

The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems, and as a result, the drawback of the carbon fine particle aggregate is that the surface of the carbon fine particle aggregate is smooth. However, if the surface is coated with a specific ultrafine particle material and the surface is roughened, the liquid phase carrying power is improved by 1.5 times or more, and the wettability with the liquid phase is significantly increased. It was found that the advantages of the carrier composed of the above-mentioned aggregate of carbon fine particles are inherited, and the present invention has been completed.

That is, the gist of the present invention is that the particle diameter selected from carbon powder, graphite powder, and powdery or spherical non-melting thermosetting resin which can be carbonized by heating is 100 μm or less and 5 μm or less. Liquid heat capable of carbonizing a fine particle material having a particle ratio of 20% or less with an ultrafine particle material selected from carbon black having a particle diameter of 1/100 or less of the particle diameter of the fine particle material and free carbon by heating. A bulk specific gravity of 0.2 to 0.5 obtained by coating with a curable resin, followed by molding, curing, firing and carbonization, followed by pulverization and classification.
A carrier for gas chromatography using a carbon fine particle aggregate having a specific surface area of 1.0 m ² / g or less by a nitrogen gas adsorption method and having a plurality of protrusions having a height of 1 μm to 20 nm on the surface.

More specifically, first, a particle diameter selected from carbon powder, graphite powder, and powdery or spherical non-melting thermosetting resin which can be carbonized by heating is 100 μm or less and 5 μm or less. 20% or less of particulate material 10
To 0 part by weight, 0.1 to 5 parts by weight of an ultrafine particle material selected from carbon black having a particle diameter of 1/100 or less of the particle diameter of the fine particle material and free carbon is added to the fine particle material by a mechanochemical method. After being adhered to the surface, 5 to 50 parts by weight of a liquid thermosetting resin which can be carbonized by heating and at least 20 parts by weight of an organic solvent are added to form a slurry, or 100 parts by weight of the fine particle material is added to 0.1 to 5 parts by weight of the particulate material, 5 to 50 parts by weight of the liquid thermosetting resin, and at least 20 parts by weight of the organic solvent are added and mixed to form a slurry.

The carbon powder and graphite powder used as the particulate material at this time are preferably those obtained by heat-treating petroleum-based or coal-based coke to obtain carbonaceous or graphite, and crushing this, and carbonizing by heating. The powdery or spherical non-melting thermosetting resin that can be used is, for example, phenol,
Examples include modified phenol and the like.

When the particle size of the fine particle material exceeds 100 μm, the bulk specific gravity of the obtained carbon fine particle aggregate is 0.5.
And the surface area decreases. Also, if the thickness is 5 μm or less, 2
If it exceeds 0%, the specific surface area of the obtained carbon fine particle aggregate exceeds 1 m ² / g, the adsorptive power becomes too large, and in either case, the separability is lowered, which is not preferable.

The ultrafine particle material coated on the surface of the fine particle material is preferably carbon black or free carbon (quinoline insoluble matter of pitches), and the particle diameter is 1/100 or less of the diameter of the fine particle material. The particulate material 100
0.1 to 5 parts by weight is used with respect to parts by weight. When the particle diameter of the ultrafine particle material exceeds 1/100 of the particle diameter of the fine particle material, there is no effect of improving the carrying force and wettability of the carrier for gas chromatography obtained in the liquid phase.

To coat the surface of the fine particle material with the ultrafine particle material, a mechanochemical method using a Reiki machine, or by dispersing the ultrafine particle material in a liquid thermosetting resin diluted with a solvent, the fine particle material is dispersed. It can also be performed by mixing with the materials.

Examples of the liquid thermosetting resin which can be carbonized by heating include phenol, modified phenol, furan and urea. Further, as the organic solvent,
Methanol, ethanol, acetone, etc. may be mentioned.

The blending amount of these is preferably in the range shown above, and when the liquid thermosetting resin is less than the lower limit, the strength of the aggregate decreases, and when it exceeds the upper limit, the bulk specific gravity of the aggregate exceeds 0.5 and separation occurs. If the ultrafine particle material exceeds 5 parts by weight, the specific surface area exceeds 1 m ² / g and less than 0.1 parts by weight, no effect is exhibited. Furthermore, when the amount of the organic solvent is small, the coating of the liquid thermosetting resin of the fine particle material is rather non-uniform, which causes a decrease in the strength of the aggregate.

Then, the slurry is dried to remove the solvent, so that the resin liquid is uniformly coated on the fine particles. At this time, it is preferable to carry out the reduced pressure drying treatment in a temperature range where the resin is not cured.

Next, this is molded. As the molding method, there are a method of extruding from a nozzle and molding into a rod shape, a molding method, and the like, but extrusion molding is particularly preferable in terms of pulverizability. The reason why the molding is performed before the heat treatment is that the aggregate obtained by the heat treatment becomes heterogeneous.

Then, the molded product is heated to 100 to 200 ° C.
And then carbonized at 1500 to 3000 ° C., crushed, and then classified to, for example, 100 to 30
A granular carbonaceous particle aggregate of 0 μm is obtained. The obtained carbon fine particle aggregate has a structure in which skeleton fine particles of 5 to 100 μm are bonded by a carbonized resin, and has a bulk specific gravity of 0.2 to 0.
5. It has a specific surface area of 1.0 m ² / g or less according to the nitrogen gas adsorption method and has a plurality of protrusions with a height of 1 μm to 20 nm on the surface, and can be suitably used as a carrier for gas chromatography.

[0018]

EFFECTS OF THE INVENTION The carbon fine powder aggregate of the present invention has a bulk specific gravity of 0.2 to 0.5, which is very small as compared with the conventional one, but has an adsorption force equal to or higher than that of the diatomaceous earth type. Since it has performance, has little variation, and is not subject to hydrolysis, it is possible to analyze a sample containing water well. Furthermore, the carbon fine particle aggregate obtained by the present invention has a plurality of protrusions with a height of 1 μm to 20 nm on the surface, and can be used as a carrier for gas chromatography for a wide range of analysis including aqueous solution analysis of high boiling point components. In addition, it has a good liquid phase holding power,
It is possible to provide a carrier for gas chromatography having improved wettability of all liquid phases.

[0019]

EXAMPLES Next, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1 5 g of commercially available carbon black having a particle diameter of 23 nm was added to 500 g of a commercially available unmelted phenol resin having a particle diameter of 30 μm and a ratio of particles having a particle diameter of 5 μm or less of 5%, and treated in a liquor machine for 1 hour. Carbon black was attached to the surface of the phenol resin by the mechanochemical method.

Next, a commercially available phenol resin liquid 100 was added to 500 g of the phenol resin to which carbon black was adhered.
g and further 300 g of methanol to make a slurry,
Dried under reduced pressure to remove methanol.

The obtained phenol resin-coated phenol resin was extruded from a nozzle having a hole diameter of 0.2 mmφ to form a rod shape, which was then heated at 150 ° C. for 2 hours to be cured,
It was baked at 2000 ° C. 80-
A carbon fine particle aggregate having a uniform particle size of 100 mesh (180 to 150 μm) was obtained.

The bulk specific gravity was 0.35, and the specific surface area measured by the nitrogen gas adsorption method was 0.7 m ² / g. Also,
When the surface was observed with a scanning electron microscope, it had a large number of protrusions on the surface as shown in FIG. 1, and its height was estimated to be 1 μm to 20 μm.

Next, Adva which is a polyester liquid phase
nce-DS (manufactured by Shinwa Kako Co., Ltd.) was loaded at 5%, and using this as a filler, methyl stearate and methyl oleate, which are esters of higher fatty acids, were analyzed. The gas chromatogram is shown in FIG. From FIG. 2, it can be seen that these higher fatty acid methyl esters can be satisfactorily separated by using the product of the present invention.

Comparative Example 1 An aggregate of carbon fine particles was obtained in the same manner as in Example 1 except that carbon black was not attached. The bulk specific gravity is 0.34, and the specific surface area by the nitrogen gas adsorption method is 0.5 m ² / g.
Met. Further, when the surface area was observed with a scanning microscope, as shown in FIG. 3, there were no protrusions on the surface and the surface was glassy.

According to the first embodiment, Advance-
DS was carried by 5%, and methyl stearate and methyl oleate were analyzed. The gas chromatogram is shown in FIG. From FIG. 4, it was not possible to completely separate methyl stearate and methyl oleate with this filler. This is the Advance of the carbon fine particle aggregate of this comparative example.
This is because the wettability with respect to e-DS is poor, and comparison between Example 1 and Comparative Example 1 revealed that the method of the present invention can improve the wettability with respect to the liquid phase.

Comparative Example 2 Example 1 except that the amount of carbon black was 50 g.
According to the above, a carbon fine particle aggregate having a uniform particle size of 80 to 100 mesh was obtained. The bulk specific gravity was 0.32, and the specific surface area measured by the nitrogen gas adsorption method was 4.3 m ² / g. Further, according to the observation with a scanning microscope, the surface had a large number of protrusions as in Example 1.

According to the first embodiment, Advance-
5% of DS was carried and methyl stearate and methyl oleate were analyzed. The gas chromatogram is shown in FIG. From FIG. 5, it became clear that methyl stearate and methyl oleate could hardly be separated with this filler.

Example 2 300 g of methanol and 10 g of carbon black having a particle diameter of 100 nm were added to 100 g of the commercially available phenol resin solution used in Example 1 and mixed for 2 hours with a ball mill to obtain a slurry in which carbon black was uniformly dispersed. It was 500g of graphite powder with particle size adjusted to 10-30μ in this slurry
Was added and mixed thoroughly to form a slurry, and then dried under reduced pressure.

The obtained phenol resin-coated graphite powder was treated according to Example 1 to obtain an aggregate of carbon fine particles having a uniform particle size of 100 to 120 mesh. This bulk specific gravity is 0.3
5 and the specific surface area by the nitrogen gas adsorption method is 0.5 m ²
/ G. Further, according to the observation with a scanning electron microscope, the surface had many protrusions.

Next, 40% of PEG-1000, which is a polyethylene glycol type liquid phase, was loaded, and using this as a filler, methanol and ethanol in the aqueous solution were analyzed. The gas chromatogram is shown in FIG. From FIG. 6, it became clear that these samples can be satisfactorily analyzed using the product of the present invention.

Comparative Example 3 An aggregate of carbon fine particles having a uniform particle size of 100 to 120 mesh was obtained in the same manner as in Example 2 except that carbon black was not added. This bulk specific gravity was 0.34, but the specific surface area by the nitrogen gas adsorption method was at a level that could not be measured.
In addition, the surface thereof was glass-like as in Comparative Example 1 when observed with a scanning microscope.

Next, 40% of PFG-1000 was carried, but this packing material had almost no fluidity and could not be packed in the column. This is because the liquid phase carrying ability of the carbon fine particle aggregate of this comparative example was low, and it was revealed from Example 2 and this comparative example that the liquid phase carrying ability can be greatly improved by the method of the present invention. .

[Brief description of drawings]

FIG. 1 is an electron micrograph showing a particle structure of a carbon fine particle aggregate of the present invention.

FIG. 2 is a gas chromatogram using the aggregate of carbon fine particles of the present invention.

FIG. 3 is an electron micrograph showing the particle structure of a carbon fine particle aggregate obtained in Comparative Example 1.

FIG. 4 is a gas chromatogram using the carbon fine particle aggregate of Comparative Example 1.

FIG. 5 is a gas chromatogram using the carbon fine particle aggregate of Comparative Example 2.

FIG. 6 is a gas chromatogram using the carbon fine particle aggregate of the present invention in Example 2.

[Explanation of symbols]

1 Acetone 2 Methyl stearate 3 Methyl oleate 4 methanol 5 ethanol 6 water

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroo Wada             2 Shin, 50, Kagekatsu-cho, Fushimi-ku, Kyoto-shi, Kyoto             Wakako Co., Ltd. (72) Inventor Kenzo Kodera             2 Shin, 50, Kagekatsu-cho, Fushimi-ku, Kyoto-shi, Kyoto             Wakako Co., Ltd.

Claims (3)

[Claims] 1. A particle diameter selected from carbon powder, graphite powder, and powdery or spherical non-melting thermosetting resin that can be carbonized by heating is 100 μm or less, and the proportion of particles having a diameter of 5 μm or less is 20%. The following fine particle materials are coated with an ultrafine particle material selected from carbon black and free carbon having a particle diameter of 1/100 or less of the particle diameter of the fine particle material and a liquid thermosetting resin that can be carbonized by heating. Then, it is molded, cured, calcined and carbonized, and then pulverized and classified to have a bulk specific gravity of 0.2 to 0.5, a specific surface area by a nitrogen gas adsorption method of 1.0 m ² / g or less and a surface of 1 μm to 20 nm
For use in gas chromatography using a carbon fine particle aggregate having a plurality of protrusions of the same height. 2. A particle diameter selected from carbon powder, graphite powder, and powdery or spherical non-melting thermosetting resin which can be carbonized by heating is 100 μm or less, and the proportion of particles of 5 μm or less is 20%. To 100 parts by weight of the following fine particle material, 0.1 to 5 parts by weight of an ultrafine particle material selected from carbon black having a particle diameter of 1/100 or less of the particle diameter of the fine particle material and free carbon is added by a mechanochemical method. And 5 to 50 parts by weight of a liquid thermosetting resin that can be carbonized by heating and at least 20 parts by weight of an organic solvent to form a slurry, which is dried and molded and cured. , Calcination and carbonization at 1500 to 3000 ° C., followed by pulverization and classification, the bulk specific gravity is 0.2 to 0.5, and the specific surface area by the nitrogen gas adsorption method is 1.
A method for producing a carrier for gas chromatography, which uses a carbon fine particle aggregate having 0 m ² / g or less and a large number of protrusions having a height of 1 μm to 20 nm on the surface. 3. A particle diameter selected from carbon powder, graphite powder and powdery or spherical non-melting thermosetting resin capable of being carbonized by heating is 100 μm or less, and the proportion of particles having a diameter of 5 μm or less is 20%. 100 parts by weight of the following fine particle material is carbonized by heating with 0.1 to 5 parts by weight of an ultrafine particle material selected from carbon black having a particle diameter of 1/100 or less of the particle diameter of the fine particle material and free carbon. 5 to 50 parts by weight of a liquid thermosetting resin capable of being treated and at least 20 parts by weight of an organic solvent are added to form a slurry, which is dried, molded, cured, calcined and carbonized at 1500 to 3000 ° C., and then crushed, Bulk specific gravity characterized by classification is 0.2 to
0.5, specific surface area by nitrogen gas adsorption method of 1.0 m ² /
A method for producing a carrier for gas chromatography using a carbon fine particle aggregate having a number of g or less and a large number of protrusions having a height of 1 μm to 20 nm on the surface.