KR20200053935A - The method of Preparing Activated Carbon of Various Shape Using Naphthalene - Google Patents

Abstract

The present invention provides a method for preparing activated carbon with various shapes using naphthalene. The method includes the steps of: pulverizing a carbonaceous material into 10 micrometers or less (based on D50); mixing the pulverized product with any one compound selected from naphthalene, toluene, furfuryl alcohol and furan resin, and an activation catalyst to form slurry; adding p-toluenesulfonic acid to the slurry mixture, and extruding or compressing the resultant mixture to mold a carbon composite with a desired shape; heat treating the molded carbon composite at 218°C or higher for 6-24 hours so that naphthalene in the molded composite may evaporate, thereby forming primary pores; and warming the molded composite having primary pores formed therein to 250-600°C and heating the same for 2-12 hours so that naphthalene in the molded composite may evaporate, thereby forming secondary pores through catalytic activation.

Description

The method of Preparing Activated Carbon of Various Shape Using Naphthalene}

The present invention relates to a method for producing activated carbon using naphthalene, and more particularly, to a method for preparing activated carbon of various shapes with minimal heat treatment by optimally mixing finely divided carbon raw materials and functional raw materials including naphthalene.

In general, activated carbon has a unique adsorption property and is widely used in various fields from daily life to industrial use.

In the prior art, a method for producing activated carbon using a coconut shell, coal-based, or wood-based carbon raw material is known, and examples thereof include the inventions described in Patent Documents 1 and 2. The invention described in the above patent publications is a technique for mixing granular activated carbon by mixing carbon-based powder and a binder, forming them using an extruder or a spheronizing device, and then activating them at 750 ° C to 1000 ° C through a carbonization heat treatment process. Is presented.

However, recently, the price of coconut shell, coal-based, and wood-based carbon raw materials, which are the main raw materials for activated carbon, has skyrocketed, and thus, domestic activated carbon manufacturers have not been able to supply low-priced raw materials, and thus have become unable to manufacture newly-made activated carbon. Due to this poor situation, domestic manufacturers recover and recycle used carbon, and then supply only low-quality regenerative activated carbon products. The carbon market is getting worse.

On the other hand, patents such as Patent Document 3 for producing activated carbon using biomass raw materials have been applied in the prior art, but it is difficult to supply and produce large quantities compared to conventional commercial raw materials, and production yields are not satisfied. to be.

Republic of Korea Patent Registration No. 10-1176587 Republic of Korea Patent Registration No. 10-0797141 Republic of Korea Patent Publication No. 2014-0070272

Therefore, the present invention has been devised to solve the limitations of the prior art described above, and by developing a new activation technology, it is possible to reduce the cost by minimizing the heat treatment process and improving the production yield dramatically by only optimal mixing of carbon raw materials and functional raw materials. It is an object of the present invention to provide a method for producing polymorphic activated carbon using naphthalene, which is capable of mass production.

In addition, the technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned are clearly understood by a person having ordinary knowledge in the technical field to which the present invention belongs from the following description. It could be.

The present invention to achieve the above object,

A step of pulverizing the carbon-based raw material to 10 µm or less (based on D50);

The pulverized product is naphthalene; Toluene; A process for producing sludge by mixing one of a compound selected from furfuryl alcohol and furan resin and an activation catalyst;

A step of adding p-toluenesulfonic acid to the sludge mixture, followed by extrusion or compression to form a carbon composite of a predetermined shape;

Heat-treating the molded carbon composite molded body at 218 ° C. or higher for 6 hours to 24 hours to volatilize naphthalene in the molded body to form primary pores; And

A process for forming secondary pores through catalyst activation by heating the molded body having the primary pores from 250 ° C to 600 ° C for 2 to 12 hours, and thus relates to a method for producing polymorphic activated carbon using naphthalene. .

The carbon-based raw material may include at least one of coconut shell, wood-based carbon raw material, coal-based carbon raw material, and biomass-based carbon raw material.

The sludge mixture, by weight, carbon-based raw material 25 to 35%; Naphthalene 25 to 35%, toluene 25 to 30%, furfuryl alcohol and furan resin may be composed of 20 to 24% of one selected from the compound and 1 to 2% of the activation catalyst.

When p-toluenesulfonic acid is added to the sludge mixture, p-toluene based on the weight of one compound selected from furfuryl alcohol and furan resin included in the mixture It is preferable to add after control so that the ratio of sulfonic acid weight may be 1: 1/8 to 1/4.

Instead of the toluene, at least one of a monocyclic aromatic compound and a benzene derivative capable of dissolving and dispersing naphthalene may be used.

The activation catalyst is preferably one or more selected from NaBH4, LiAlH4, KOH.

It is preferable to heat in an inert atmosphere or a reducing atmosphere in the secondary pore forming process.

According to the present invention having the configuration as described above, through the optimum mixing ratio of various carbon-based raw materials and functional raw materials, activated carbon can be produced only with minimal heat treatment, and can also be easily molded into various shapes, so that it is suitable for various preferences of the buyer. It can also give a distinctive decorative effect. In addition, as the heat treatment process is minimized, the production yield is also dramatically improved, so manufacturing cost can be reduced. In addition, since the activation heat treatment process is minimized, not only the shape of the product can be maintained, but also high-strength properties can be provided, and thus activated carbon that can be recycled for a long time can be provided.

1 is a flow chart of a manufacturing process of a polymorphic activated carbon according to an embodiment of the present invention.
2 is a perspective view showing a polymorphic activated carbon prepared according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail.

The method for producing polymorphic activated carbon using naphthalene of the present invention includes a step of pulverizing a carbon-based raw material to 10 µm or less (based on D50); The pulverized product is naphthalene; Toluene; A process for producing sludge by uniformly mixing one type of compound selected from furfuryl alcohol and furan resin and an activation catalyst; A step of adding p-toluenesulfonic acid to the sludge mixture, followed by extrusion or compression to form a carbon composite of a predetermined shape; Heat-treating the molded carbon composite molded body at 218 ° C. or higher for 6 hours to 24 hours to volatilize naphthalene in the molded body to form primary pores; And heating the molded body in which the primary pores are formed from 250 ° C to 600 ° C and heating them for 2 to 12 hours to form secondary pores through catalyst activation.

1 is a flow chart of a process for producing activated carbon according to an embodiment of the present invention.

As shown in Fig. 1, the carbon-based raw material is pulverized to 10 µm or less (based on D50).

In the present invention, it is preferable to manufacture within the conditions of the present invention as follows, since it affects the pore amount, the size of the pores, and the production yield according to the crushing particle size and blending ratio of the carbon-based raw material.

First, in the crushing process, the carbon-based raw material is pulverized to 10 µm or less (based on D50). At this time, in the present invention, any carbon-based raw material that can be used as a carbon-based raw material can be used, but preferably, one of palm-based, wood-based, coal-based, and biomass-based raw materials is used.

In addition, the present invention is not limited to a specific method for pulverizing the carbon-based raw material, and any method for pulverizing the particle diameter to 10 µm or less can be used. In the present invention, as the carbon-based raw material has more nano-sized particles, an effect of increasing the iodine value of activated carbon can be obtained. However, if the pulverized particle size exceeds 10 µm (based on D50), the pulverized carbon-based raw material may generate cracks in the produced activated carbon, and may interfere with pore formation.

More preferably, the carbon-based raw material is pulverized to 5 µm or less (based on D50).

Then, in the present invention, the pulverized product is naphthalene (naphthalene); Toluene; A sludge is prepared by uniformly mixing one type of compound selected from furfuryl alcohol and furan resin and an activation catalyst.

In the mixing process, a sludge mixture is prepared by uniformly mixing the pulverized material as a functional raw material of naphthalene, toluene, furfuryl alcohol or furan resin, and an activation catalyst for 20 to 30 minutes. The more uniformly the mixture is dispersed, the more uniform the activation is, the more open micropores are developed and the effect of improving the strength of the prepared activated carbon can also be obtained.

At this time, the sludge mixture in the present invention, by weight, carbon-based raw material 25 to 35%; Naphthalene 25 to 35%, toluene 25 to 30%, it is preferably composed of 20 to 24% of a compound selected from furfuryl alcohol and furan resin and 1 to 2% of an activation catalyst.

 Further, in the present invention, instead of the toluene, at least one of a monocyclic aromatic compound (for example, xylene, etc.) and a benzene derivative (for example, amine aniline, etc.) capable of dissolving and dispersing naphthalene may be used.

The activation catalyst is preferably one or more selected from NaBH4, LiAlH4, KOH.

In the present invention, p-toluenesulfonic acid is added to the sludge mixture, and then extruded or compressed to form a carbon composite having a predetermined shape. In this molding process, p-toluene sulfonic acid may be added to the mixture and then inserted into various types of molds, or the carbon composite material may be manufactured in various shapes through an extruder or a compression molding machine.

In the present invention, when p-toluenesulfonic acid is added to the sludge mixture, the weight of one compound selected from furfuryl alcohol and furan resin contained in the mixture is added. It is preferable to add after controlling the ratio of the weight of p-toluene sulfonic acid to 1: 1/8 to 1/4. At this time, p-toluene sulfonic acid, furfuryl alcohol, toluene reacts with carbonization to occur, and the mixture is cured to form a carbon complex as shown in Reaction Scheme 1.

[Scheme 1]

C _x H _x + C ₁₀ H ₈ + C ₇ H ₈ + C ₅ H ₆ O ₂ + KOH + C ₇ H ₈ O ₂ S

→ [-(C _x H _x )-(C ₁₀ H ₈ )-(C ₇ H ₈ )-(C ₅ H ₆ O ₂ )-(C ₇ H ₈ O ₂ )-] _n + KOH + S ↑ ( Room temp.)

Here, KOH is an activation catalyst, furfuryl alcohol (C ₇ H ₈ O ₂ S) is a polymerization catalyst, and x, y, and z in the reaction formula can be changed depending on the properties and reaction temperature of carbon raw materials, mixing conditions, and the like.

If the p-toluene sulfonic acid is added in excess of 1/4 of the weight ratio, the mixture is rapidly cured before molding, so that the desired shape cannot be obtained, and when activated, cracks may occur in the molded body, which may cause manufacturing costs to rise. Can be. On the other hand, when the p-toluene sulfonic acid is introduced in a weight ratio of less than 1/8, partial curing occurs because curing does not occur slowly or does not uniformly disperse, so that the desired shape cannot be obtained and sufficient strength cannot be formed.

At this time, in the present invention, since the p-toluene sulfonic acid is cured immediately after input, it is preferable to insert it into a mold within 10 minutes, or to extrude or compress it. Accordingly, it is preferable to add p-toluene sulfonic acid immediately before molding. In addition, molds of various materials such as rubber, urethane, plastic, and stainless steel can be used to manufacture activated carbon of various shapes, and various devices such as compressors and extruders can be used.

Subsequently, in the present invention, the molded carbon composite molded body is heat treated at 218 ° C. or higher for 6 hours to 24 hours to volatilize naphthalene in the molded body to form primary pores, as shown in Reaction Scheme 2 below. In this activation process, in order to form pores in the molded product which is the carbon composite, heat treatment is performed at 218 ° C. or higher, which is a volatilization temperature of naphthalene, to volatilize naphthalene to form primary pores. More preferably, it is to increase the efficiency of removing naphthalene by heat treatment in a temperature range of 218 to 250 ° C.

[Scheme 2]

[-(C _x H _x )-(C ₁₀ H ₈ )-(C ₇ H ₈ )-(C ₅ H ₆ O ₂ )-(C ₇ H ₈ O ₂ )-] _n + KOH

→ [-(C _x H _x )-(C _y H _y O _y )-] _n + KOH + C ₁₀ H ₈ ↑ + C ₇ H ₈ ↑ (218 ℃ ~ 250 ℃)

Finally, in the present invention, the secondary pores are formed through catalyst activation, as shown in the following Reaction Scheme 3, by heating the molded body formed with the primary pores from 250 ° C. to 600 ° C. for 2 to 12 hours.

[Scheme 3]

[-(C _x H _x )-(C _y H _y O _y )-] _n + KOH

→ [-(C)-(C _xz H _xz )-(C _yz H _yz O _yz )-] _z + K ₂ CO ₃ + CO ₂ ↑ + H ₂ ↑

After removing naphthalene, it is necessary to heat from 250 ° C to 600 ° C to heat for 2 to 12 hours so that it can be activated by the added catalyst to form additional secondary pores. For example, if it is less than 218 ° C, naphthalene does not volatilize, and at 600 ° C or higher under the influence of a catalyst, the molded product reacts rapidly and is oxidized, so production yields may decrease or cracks may occur, which may have a negative effect. In particular, it is more preferable to heat in an inert atmosphere or a reducing atmosphere since an activation reaction occurs by a functional raw material and a catalyst from 250 ° C to 600 ° C in which catalyst activation occurs, and an oxidation reaction also occurs.

Meanwhile, a tube furnace may be used as the heat treatment device, and it is preferable to use Tunnel Kiln, Roller Hearth Kiln, Pusher Hearth Kiln, etc. for continuous production. In addition, it is preferable to use a mesh tray or a perforated tray for uniform heat treatment and activation of the molding. In addition, if the unreacted toluene or naphthalene volatilized during the heat treatment process is collected and recycled, the effect of cost reduction can be obtained.

Thereafter, the polymorphic activated carbon thus prepared may be washed with water to remove impurities, and the cleaning method is not limited.

According to the present invention having the above-described configuration, it is possible to produce polymorphic activated carbon with only minimal heat treatment through an optimum mixing ratio of various carbon-based raw materials and functional raw materials.

Hereinafter, the present invention will be described in detail through examples.

(Example 1)

First, Green Coke, a coal-based carbon raw material, was pulverized to 10 µm based on D50 using a coarse and fine pulverizer. 25% by weight of pulverized green coke, 24% by weight of furfuryl alcohol, 24% by weight of toluene, 25% by weight of naphthalene, and 2% by weight of KOH, which is an activation catalyst, were uniformly mixed in a slurry state for 30 minutes. After adding 6% by weight of p-toluene sulfonic acid in a ratio of 1/4 weight to the weight of furfuryl alcohol contained in the mixed slurry, the mixture was compressed into molds of various shapes to effect carbonization and molded into carbon composites of various shapes. The carbon composite thus formed is heat treated at 250 ° C. for 1 hour in a tube furnace to volatilize naphthalene in the molded body to form primary pores, and heated to 10 ° C./min to activate the catalyst for 12 hours in a nitrogen atmosphere at 500 ° C. for secondary pores. To form an active carbon maintaining a variety of shapes as shown in Figure 2.

Carbon raw material size
(Based on D50) (㎛) Carbon raw material
Kinds Iodine
(mg / g) Shore hardness
(hs) Manufacturing yield
(%) Example 1 9.64 Green Coke 865 ~ 885 7 ~ 21 53 Example 2 0.93 Green Coke 913 10 ~ 22 51 Example 3 9.57 Coconut shell 1,011 3 ~ 12 41 Comparative Example 1 9.60 Green Coke 860 6 ~ 15 30 Comparative Example 2
(Commercial goods for air purifiers) - Coconut shell 882 0 ~ 9 -

Iodine value (KS M-1802 standard), strength (Shore hardness tester), and production yield, which are representative measuring methods of adsorption performance, were measured for the polymorphic activated carbon prepared as described above, and the results are shown in Table 1 above.

As shown in Table 1, it can be seen that the polymorphic activated carbon produced by the method of the present invention exhibits an iodine number similar to that of a commercial product for an air purifier. In addition, it can be seen that even when compared with activated carbon produced in a commercial process, shore hardness and production yield are significantly improved.

(Example 2)

In Example 2, a test was performed using green coke of 0.93 µm (d50) as a carbon raw material, and activated carbon was prepared in the same manner as in Example 1. As shown in Table 1, it can be confirmed that the smaller the particle size of the carbon raw material, the higher the iodine value.

(Example 3)

In Example 3, a test was conducted using coconut shell as a carbon raw material, and activated carbon was prepared in the same manner as in Example 1. As shown in Table 1, it can be seen that the activated carbon using coconut shell as a raw material has a higher iodine value than the case where green coke is used as a raw material, but the production yield is somewhat reduced.

(Comparative Example 1)

In Comparative Example 1, coal-based green coke was used as a carbon raw material, mixed with a binder in a commercial process, and extruded into pellets, followed by a calcination heat treatment and an activation process to produce pellet activated carbon. As a commercial process, it can be confirmed that the iodine value is equal when manufacturing, but the production yield is significantly lowered.

(Comparative Example 2)

The iodine number and shore hardness of commercially available activated carbon for air cleaners (L company) were measured.

As described above, in the detailed description of the present invention, the preferred embodiments of the present invention have been described, but those skilled in the art to which the present invention pertains have various modifications within the limits that do not depart from the scope of the present invention. Of course this is possible. Therefore, the scope of rights of the present invention should not be determined by being limited to the described embodiments, but should be determined by the equivalents as well as the claims described later.

Claims (7)

A step of pulverizing the carbon-based raw material to 10 µm or less (based on D50);
The pulverized product is naphthalene; Toluene; A process for producing sludge by mixing one of a compound selected from furfuryl alcohol and furan resin and an activation catalyst;
A step of adding p-toluenesulfonic acid to the sludge mixture, followed by extrusion or compression to form a carbon composite of a predetermined shape;
Heat-treating the molded carbon composite molded body at 218 ° C. or higher for 6 hours to 24 hours to volatilize naphthalene in the molded body to form primary pores; And
Method for forming a secondary pore through catalytic activation by heating the molded body formed with the primary pores from 250 ° C. to 600 ° C. for 2 hours to 12 hours to produce polymorphic activated carbon using naphthalene.
The method of claim 1, wherein the carbon-based raw material comprises at least one of a palm shell, a wood-based carbon raw material, a coal-based carbon raw material, and a biomass-based carbon raw material.
According to claim 1, The sludge mixture, by weight, carbon-based raw material 25 to 35%; Naphthalene is used, which is characterized by comprising 25 to 35% of naphthalene, 25 to 30% of toluene, 20 to 24% of a compound selected from furfuryl alcohol and furan resin, and 1 to 2% of an activation catalyst. Shape activated carbon production method.
According to claim 1, When adding the p-toluenesulfonic acid (p-toluenesulfonic acid) to the sludge mixture, one compound selected from the furfuryl alcohol (furfuryl alcohol) and furan resin (Furan resin) contained in the mixture Method for producing polymorphic activated carbon using naphthalene, characterized in that the ratio of p-toluene sulfonic acid weight to weight ratio is 1: 1/8 to 1/4, and then added.
The method according to claim 1, wherein at least one of a monocyclic aromatic compound and a benzene derivative capable of dissolving and dispersing naphthalene is used instead of the toluene.
[6] The method of claim 1, wherein the activation catalyst is at least one selected from NaBH4, LiAlH4, and KOH.
The method of claim 1, wherein in the secondary pore forming step, heating is performed in an inert atmosphere or a reducing atmosphere.

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