JP3713062B2 - Activated carbon and method for producing the same - Google Patents

Description

ところで、図２に示すように、実施例の中間生成物と比較例のそれとは細孔直径の分布に違いがあった。すなわち、細孔直径が１〜１０μｍ程度の吸着にあまり有効でない範囲では、明らかに実施例は比較例より孔の体積が少なく、逆に細孔直径が０．１μｍ以下の有効に吸着効果を持つミクロポアーは、やや多い傾向が見られた。したがって、本実施例では、吸着に関与しないマクロポアーの量が減少し、有効に吸着に関与するミクロポアーの比率が若干増加していた。それゆえに本発明の活性炭は、体積当たりの吸着能力が向上していたと考えられる。
【００１９】
ちなみに、図２のグラフの縦軸は、最小区間の細孔（ミクロポアー）容積の微分値で、中間生成物の細孔分布を表し、その単位は〔ｃｃ／ｇ〕である。
以上詳述したように、本発明の活性炭およびその製造方法によれば、孔中に付加活性炭成分を保持した活性炭が提供されたので、活性炭の容積当たりの吸着性能を向上させ、更にはその硬度低下を少なく抑えることができたことが分かる。
【００２０】
（中間生成物としての基材炭素の比較）
なお参考までに、前述の実施例中で基材炭素製造工程１を終えた中間生成物１としての基材炭素と、同様に前述の比較例中で基材炭素製造工程を終えた中間生成物２としての基材炭素の物性値を、表２に比較して示す。
ここで、中間生成物１としての基材炭素は、その後、含浸工程２、乾留工程３１および賦活工程３２を経て、本発明の実施例としての活性炭に加工されるべきものであった。一方、中間生成物２としての基材炭素は、その後、従来の賦活工程のみを施されて、比較例としての従来の活性炭に加工されるべきものであった。
【００２１】
表２において、両者の物性値の違う理由は、中間生成物内部にあるマクロポアーに含炭素成分を形成させ、空洞を減らして容積当たりの密度を増加させる為である。ここで、中間生成物１はタール含浸物、中間生成物２は未含浸のものである。特に充填密度が異なる理由は、中間生成物内部にある空洞内を含炭素成分で減少させ、容積当たりの密度を増加させる為である。その意図するところは、その後の賦活工程において高密度な乾留炭を使用することで、容積当たりの吸着性能および硬度を向上させることにある。
【００２２】
なお、バインダー含浸後の中間生成物１は、比較例（一般品）の中間生成物２と異なった物性であるが、これは含浸を行ったことにより生じた差であり、含浸を行う前の乾留炭は全く同じ物を使用していることから、含浸効果が確認できる。
【００２３】
【表２】

【００２４】
【発明の効果】
本発明の活性炭およびその製造方法によれば、孔中に付加活性炭成分を保持した活性炭が提供されるので、活性炭の容積当たりの吸着性能を向上させ、更にはその硬度低下を少なく抑えることができる。
【図面の簡単な説明】
【図１】本発明の活性炭の製造方法を示すブロック図
【図２】本発明の活性炭の細孔の分布を示すグラフ
【図３】従来の活性炭の製造方法を示すブロック図
【符号の説明】
１：基材炭素製造工程 ２：含浸工程 ３：炭化工程
３１：乾留工程 ３２：賦活工程[0001]
[Industrial application fields]
The present invention relates to an activated carbon having a high density, a high adsorption capacity per volume, and a low hardness reduction, and a production method thereof.
[0002]
[Prior art]
Conventionally, as shown in FIG. 3, a conventional method for producing activated carbon pulverizes a carbon-containing substance typified by a coal raw material, mixes it with a binder, kneads it, and then raises the temperature. This is a method for producing porous activated carbon by activating the base carbon obtained by sieving the carbonized carbonized product.
[0003]
Such a manufacturing method or a similar manufacturing method is disclosed in Japanese Patent Application Laid-Open No. 4-21511 and Japanese Patent Application Laid-Open No. 6-100311, and the characteristics of activated carbon manufactured by such a manufacturing method are also disclosed. It has been announced.
[0004]
[Problems to be solved by the invention]
However, in the activated carbon according to the conventional manufacturing method, pores are widely formed from the micropore to the macropore (average diameter of about 0.1 to 50 μm) during activation, and the strength is reduced. Furthermore, the increase in macropores that are not involved in adsorption reduces the adsorption performance per volume. That is, the activated carbon produced by the conventional manufacturing method has a problem in that the adsorption performance per volume is limited and there is a considerable decrease in hardness.
[0005]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an activated carbon having improved adsorption performance per volume of activated carbon and further suppressing the decrease in hardness and a method for producing the activated carbon.
[0006]
[Means for Solving the Problems]
The present invention is based on the discovery that an additional activated carbon component can be formed in the pores (inside the macropores) present in the base carbon by impregnating the porous base carbon with a liquid containing a carbon component and carbonizing it. It was made based on.
That is, the activated carbon of the present invention is characterized by comprising base carbon formed of porous activated carbon and an additional activated carbon component introduced and held in the pores of the base carbon.
[0007]
The method for producing activated carbon of the present invention includes an impregnation step of impregnating a liquid containing a carbon component into pores of a porous base carbon to form an impregnated base carbon, heating the impregnated base carbon, and the carbon component And carbonizing step of adding activated carbon component.
Here, the base carbon can be produced by finely pulverizing a carbon-containing material to form a fine powder, heating a molded product obtained by kneading and forming a binder into the fine powder, and carbonizing and carbonizing. it can. Further, the carbon-containing material may be any one of coal, coconut shell, wood, or formed coal. Furthermore, it is desirable that the liquid containing the carbon component in the impregnation step is a coal-based binder. The ratio of impregnating the liquid containing the carbon component is suitably in the range of 3 to 50 parts by weight with respect to 100 parts by weight of the base carbon.
[0008]
By the way, in the method for producing activated carbon, it is desirable that the carbonization step includes a dry distillation step and an activation step. The former dry distillation step is a step of raising the temperature from room temperature to 400 ° C or higher in a nitrogen atmosphere, and the latter activation step is more in line with the above-mentioned purpose if it is a step of heating in a steam atmosphere. Activated carbon can be produced.
[0009]
According to such a method for producing activated carbon of the present invention, the above-described activated carbon of the present invention can be produced.
[0010]
[Action]
In the method for producing activated carbon according to the present invention, a liquid containing a carbon component is impregnated in the pores of the porous substrate carbon (particularly in the macropores), and then the liquid containing the carbon component is carbonized to obtain an additional activated carbon component. . As a result, an activated carbon is produced which is composed of a base carbon formed of porous activated carbon and an additional activated carbon component introduced and held in the pores of the base carbon. In the activated carbon of the present invention thus produced, the additional activated carbon component is held in the macropore to reduce the diameter of the pores, thereby forming an adsorptive micropore and realizing a high strength structure.
[0011]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
(Example)
The flow of the method for producing activated carbon as an embodiment of the present invention is shown in FIG. This production method includes an impregnation step 2 in which a porous substrate carbon produced in the base carbon production step 1 is impregnated with a liquid containing a carbon component to form an impregnation base carbon, and the impregnation base material And carbonization step 3 in which carbon is heated to carbonize the carbon component to obtain an additional activated carbon component.
[0012]
Said base carbon manufacturing process 1 is a process which consists of the fine grinding | pulverization process 11, the kneading | mixing process 13, the shaping | molding process 14, the dry distillation process 15, and the sieving process 15 in order, and manufactures porous base carbon.
First, in the fine pulverization step 11, the coal material 10 as a carbon-containing substance was pulverized with a known fine pulverizer such as a bantam mill to form a fine powder. Next, in the kneading step 13, 100 parts by weight of the fine powder was blended and kneaded at a ratio of 30 parts by weight of a pitch-type binder to produce a kneaded product. Then, the kneaded product formed in the molding step 14 was carbonized and carbonized by heating at a rate of 2.5 ° C. per minute from room temperature to 700 ° C. in a nitrogen atmosphere in the next carbonization step 15. Substrate carbon was obtained by sieving the dry distillate thus obtained in the sieving step 16.
[0013]
Thus, the base carbon in which pores are formed in a wide range from the micropore to the macropore is manufactured by the base carbon manufacturing process 1, and the impregnation process 2 and the subsequent carbonization process 3 which are the center of the present invention. Served as raw material.
In the impregnation step 2, 20 parts by weight of coal tar as a liquid containing a carbon component was impregnated into the base carbon at room temperature. Then, coal tar soaked into the macropores in the base carbon, and impregnated base carbon that retained coal tar containing carbon in the macropores was generated.
[0014]
The carbonization step 3 includes a dry distillation step 31 and an activation step 32. In the carbonization step 31, the impregnated base carbon is heated at a rate of 2.5 ° C. per minute from room temperature to 700 ° C. in a nitrogen atmosphere, as in the dry distillation step 15 of the base carbon production step 1 described above. The coal tar impregnated in the base carbon was carbonized and carbonized. And in the activation process 31, the product of the said carbonization process 31 which hold | maintained the carbon content of carbonized carbonized coal tar in the macropore in base carbon was activated at 950 degreeC for 6 hours in water vapor | steam atmosphere.
[0015]
In such an activated carbon production method of the present invention, there is a difference in that an impregnation step 2 and a dry distillation step 31 are newly added as compared with the conventional production method. Thus, as an embodiment of the present invention, characterized in that it consists of a base carbon formed of porous activated carbon and an additional activated carbon component introduced and held in the pores (inside the macropores) of the base carbon. Activated carbon was produced.
[0016]
(Comparative example)
In order to compare with the activated carbon produced by the production method of the present invention described above, activated carbon was produced by a production method according to the prior art in which the impregnation step 2 and the dry distillation step 31 which are features of the present invention were omitted. That is, the same carbon raw material as in the above-mentioned examples is treated in the same base carbon production process and carbonized carbonized base carbon is subjected to the same activation step without impregnation carbonization to produce activated carbon as a comparative example. did.
[0017]
(Comparison evaluation)
In Table 1, activated carbon as an example of the present invention manufactured by applying the impregnation step 2 and the carbonization step 3 which are features of the present invention to the base carbon as described above, The physical property values of activated carbon as a comparative example manufactured by a conventional manufacturing method in which only the activation step (the activation degree is the same as in the examples) are compared and listed. From this table, it is clear that the activated carbon of this example was superior to that of the comparative example in any of benzene adsorption amount, hardness, specific surface area, and pore distribution.
[0018]
[Table 1]

Incidentally, as shown in FIG. 2, there was a difference in pore diameter distribution between the intermediate product of the example and that of the comparative example. That is, in the range where the pore diameter is not so effective for adsorption having a pore diameter of about 1 to 10 μm, the examples obviously have a smaller pore volume than the comparative example, and conversely, the pore diameter is effectively less than 0.1 μm. Micropores were slightly more prone. Therefore, in this example, the amount of macropores not involved in adsorption decreased, and the proportion of micropores effectively involved in adsorption slightly increased. Therefore, the activated carbon of the present invention is considered to have improved adsorption capacity per volume.
[0019]
Incidentally, the vertical axis of the graph of FIG. 2 is the differential value of the pore (micropore) volume in the minimum section, and represents the pore distribution of the intermediate product, and its unit is [cc / g].
As described above in detail, according to the activated carbon of the present invention and the method for producing the same, activated carbon having the additional activated carbon component retained in the pores is provided, so that the adsorption performance per volume of the activated carbon is improved, and further its hardness It can be seen that the decrease could be reduced.
[0020]
(Comparison of substrate carbon as an intermediate product)
For reference, the base carbon as the intermediate product 1 that has completed the base carbon manufacturing process 1 in the above-described examples, and the intermediate product that has similarly completed the base carbon manufacturing process in the above-described comparative example. The physical property values of the base carbon as 2 are shown in comparison with Table 2.
Here, the base carbon as the intermediate product 1 was to be processed into activated carbon as an example of the present invention through the impregnation step 2, the dry distillation step 31 and the activation step 32. On the other hand, the base carbon as the intermediate product 2 was to be processed into conventional activated carbon as a comparative example after being subjected only to the conventional activation step.
[0021]
In Table 2, the reason why the physical property values of the two are different is that the carbon-containing component is formed in the macropores in the intermediate product, the voids are reduced, and the density per volume is increased. Here, the intermediate product 1 is a tar impregnated product, and the intermediate product 2 is an unimpregnated product. The reason why the packing density is particularly different is that the inside of the intermediate product is reduced by the carbon-containing component to increase the density per volume. The intention is to improve adsorption performance and hardness per volume by using high-density carbonized carbon in the subsequent activation process.
[0022]
The intermediate product 1 after impregnation with the binder has different physical properties from the intermediate product 2 of the comparative example (general product), but this is a difference caused by the impregnation and before the impregnation. Since the same carbonized carbon is used, the impregnation effect can be confirmed.
[0023]
[Table 2]

[0024]
【The invention's effect】
According to the activated carbon and the method for producing the same of the present invention, the activated carbon having the additional activated carbon component retained in the pores is provided, so that the adsorption performance per volume of the activated carbon can be improved, and further the decrease in hardness can be suppressed to a small extent. .
[Brief description of the drawings]
FIG. 1 is a block diagram showing a method for producing activated carbon of the present invention. FIG. 2 is a graph showing a distribution of pores in the activated carbon of the present invention. FIG. 3 is a block diagram showing a conventional method for producing activated carbon.
1: Substrate carbon production process 2: Impregnation process 3: Carbonization process 31: Dry distillation process 32: Activation process

Claims (7)

Activated carbon that has been steam activated,
A base carbon formed of porous activated carbon, and an additional activated carbon component in which the carbon component introduced and held in the pores of the base carbon is dry-distilled and activated ,
Compared to activated carbon as a comparative example in which the steam activation treatment is similarly performed but the additional activated carbon component is not introduced and held in the pores, the adsorption capacity per volume is higher, and the decrease in hardness is suppressed to a small extent. Activated carbon characterized by Activated carbon that has been steam activated,
A base carbon formed of porous activated carbon, and an additional activated carbon component in which the carbon component introduced and held in the pores of the base carbon is dry-distilled and activated ,
Compared to activated carbon as a comparative example in which the water vapor activation treatment is similarly performed but the additional activated carbon component is not introduced and held in the pores, the benzene adsorption amount, packing density, hardness, nitrogen BET method specific surface area and Activated carbon characterized by high methanol pore distribution. An impregnation step of impregnating a liquid containing a carbon component into the pores of the porous base carbon to make the base carbon impregnated;
The impregnated base carbon is heated, and the carbon component is carbonized to form an additional activated carbon component,
The carbonization step comprises a dry distillation step and an activation step of heating in a steam atmosphere,
A method for producing activated carbon. The base carbon is produced by finely pulverizing a carbon-containing substance to form a fine powder, heating a molded product obtained by kneading and forming a binder in the fine powder, and carbonizing and carbonizing.
The manufacturing method of the activated carbon of Claim 3 . The carbon-containing substance is any one of coal, coconut shell, wood, or formed coal.
The manufacturing method of the activated carbon of Claim 4 . The liquid containing the carbon component is a coal-based binder.
The manufacturing method of the activated carbon of Claim 3 . The carbonization step is a step of raising the temperature from room temperature to 400 ° C or higher.
The manufacturing method of the activated carbon of Claim 3 .

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