KR101407506B1 - Method for heat treatment of carbon raw materials for activated carbons - Google Patents

Abstract

The present invention relates to a method for producing activated carbon, and more particularly, to a method for producing activated carbon, which comprises adding 100 parts by weight to 200 parts by weight of an alkali salt to 100 parts by weight of a carbon raw material. Subjecting the mixture to a heat treatment at 300 ° C to 500 ° C; And 100 parts by weight to 400 parts by weight of an alkali salt with respect to 100 parts by weight of the heat-treated mixture, thereby activating carbon.

Activated carbon, carbon raw material, alkali salt, heat treatment, activation

Description

METHOD FOR HEAT TREATMENT OF CARBON RAW MATERIALS FOR ACTIVATED CARBONS

More particularly, the present invention relates to a method for producing activated carbon, and more particularly, to a method for producing activated carbon, which comprises adding 100 to 200 parts by weight of an alkali salt to 100 parts by weight of a carbon raw material, To a method for producing activated carbon having a high yield and a high capacitance.

Since the capacitance of the capacitor is mainly controlled by the surface area of the electrode and the electrode resistance per unit area, it is important to increase the density of the electrode itself in order to increase the capacitance per unit volume and reduce the volume of the electric double layer capacitor Do.

Activated carbon used for conventional capacitors can be produced by activating raw materials such as coal, coal coke, wood, coconut shell, and pitch under acidic conditions such as water vapor and gas or by activating them with a strong oxidizing agent such as potassium hydroxide .

In relation to the pretreatment, preparation of fixed total capacity activated carbon per volume, 1A06, 30th Annual Meeting of the Society of Carbon Materials (2003, Japan Carbon Society), the carbon raw material was pretreated at 800 ° C and activated at 700-900 ° C A method of producing activated carbon having a high electrostatic capacity has been reported.

However, in the case of performing the preheating treatment by this production method, there is a disadvantage that the expensive alkaline salt used by the non-uniform mixing of the carbon raw material and the alkali salt can not be sufficiently exhibited.

Therefore, in order to solve such a problem, the present invention provides a method for pretreating a carbonaceous raw material having a high electrostatic capacity by mixing a carbonaceous raw material with a certain amount of an alkali salt, inducing homogeneous mixing through a preheating treatment, adding an additional alkali salt, The purpose is to provide.

In order to achieve the above object,

As a first aspect, there is provided a method for producing a carbonaceous material, which comprises adding 100 parts by weight to 200 parts by weight of an alkali salt to 100 parts by weight of a carbon raw material;

Subjecting the mixture to a heat treatment at 300 ° C to 500 ° C; And

Adding 100 parts by weight to 400 parts by weight of an alkali salt to 100 parts by weight of the heat-treated mixture to activate the mixture;

Wherein the method comprises the steps of:

According to a second aspect, the present invention provides a carbon raw material pretreatment method for producing activated carbon, wherein the carbon raw material is a coal-based, petroleum-based, or wood-based carbon raw material.

As described above, according to the method of the present invention, activated carbon having a high yield and capacitance can be produced by pretreating a carbon raw material for producing activated carbon.

Hereinafter, the present invention will be described in more detail.

The pretreatment method for the carbon raw material for the activated carbon production of the present invention includes the step of adding an alkali salt to the carbon raw material.

The above-mentioned carbon raw materials may be those which are commonly used, and examples thereof include carbonaceous, petroleum-based or woody carbonaceous raw materials, though not particularly limited.

The alkali salt added to the carbon raw material is added in an amount of 100 parts by weight to 200 parts by weight based on 100 parts by weight of the carbon raw material. If it is added in an amount of more than 200 parts by weight, the carbon may be partially converted into a carbonate form in the temperature range of 150 ° C to 300 ° C by the following reaction, The yield is lowered.

_{C + 2NaOH + H 2 O =} 2H 2 + Na 2 CO 3

Next, the carbon raw material pretreatment method of the present invention includes a step of heat-treating the mixture of the carbon raw material and the aqueous alkaline solution.

The heat treatment is preferably performed in a temperature range of 300 ° C to 500 ° C. Since sodium hydroxide has a melting point of about 300 ° C to 328 ° C depending on whether it contains a small amount of water and a melting point of potassium hydroxide is 360 ° C, it is preferable to perform the heat treatment at 300 ° C or more for melting the alkali salt. Further, in order to impart a sufficient degree of fluidity to the molten alkali salt to enable uniform mixing with the carbon raw material, it is preferable to carry out a heat treatment at a temperature of 500 ° C or lower. When the temperature is higher than 500 ° C, It is preferable to perform the heat treatment at a temperature range of 300 to 500 ° C.

Further, the method for pretreating a carbonaceous material of the present invention includes the step of further adding an alkali salt to a mixture of the heat-treated carbonaceous material and an aqueous alkali solution to activate the mixture.

The activation method is not particularly limited and can be carried out by a conventional method for the pretreatment of the carbon raw material. Those skilled in the art will understand the activation method.

The alkali salt preferably ranges from 100 parts by weight to 400 parts by weight based on 100 parts by weight of the mixture of the heat-treated carbon raw material and the alkali aqueous solution. When the alkali salt is added in an amount of less than 100 parts by weight, sufficient alkali activation can not be expected. When the alkali salt is added in an amount exceeding 400 parts by weight, the effect of addition can not be expected and the yield of activated carbon is lowered. It is preferable to further add in the range.

The method for pretreating a carbon source according to the method of the present invention can produce an activated carbon having an excellent electrostatic capacity by inducing efficient activation of a carbon source by uniformly mixing a raw material and an alkali salt.

Hereinafter, the present invention will be described more specifically by way of examples. However, it should be understood that the present invention is not limited by the following examples.

Example

Comparative Example  One

Activated carbon was prepared by adding 350 parts by weight of NaOH to 100 parts by weight of coal pitch, without adding NaOH and performing a pretreatment of heat treatment, followed by activation at 900 ° C by a conventional method. The yield and the electrostatic capacity of the activated carbon were measured. The results are shown in Table 1 below.

Comparative Example  2

50 parts by weight of NaOH was added to 100 parts by weight of coal pitch, and the mixture was heated to 400 DEG C and cooled. 300 parts by weight of NaOH was further added to the heat-treated mixture and activated at 900 DEG C by a conventional method to produce activated carbon . The yield and the electrostatic capacity of the activated carbon were measured. The results are shown in Table 1 below.

Example  One

100 parts by weight of NaOH was added to 100 parts by weight of coal pitch, and the mixture was heated to 400 DEG C and cooled. Then, 250 parts by weight of NaOH was further added to the heat treatment mixture and activated at 900 DEG C by a conventional method to produce activated carbon. The yield and the electrostatic capacity of the activated carbon were measured. The results are shown in Table 1 below.

Example  2

200 parts by weight of NaOH was added to 100 parts by weight of coal pitch, and the mixture was heated to 400 DEG C and cooled. Then, 150 parts by weight of NaOH was further added to the heat treatment mixture and activated at 900 DEG C by a conventional method to produce activated carbon. The yield and the electrostatic capacity of the activated carbon were measured. The results are shown in Table 1 below.

Comparative Example  3

250 parts by weight of NaOH was added to 100 parts by weight of coal pitch, and the mixture was heated to 400 DEG C and cooled. Then, 100 parts by weight of NaOH was further added to the heat treatment mixture and activated at 900 DEG C by a conventional method to produce activated carbon. The yield and the electrostatic capacity of the activated carbon were measured. The results are shown in Table 1 below.

Pretreatment NaOH
Additional added amount
(Parts by weight) yield
(%) Capacitance
(F / cc)) NaOH addition amount
(Parts by weight) Temperature
(° C) Comparative Example 1 - - 350 51.8 53.8 Comparative Example 2 50 400 300 72.6 52.8 Example 1 100 400 250 68.3 62.4 Example 2 200 400 150 65.4 64.7 Comparative Example 3 250 400 100 54.7 62.8

As shown in the above table, when the preprocessing is not performed (Comparative Example 1), it can be seen that the electrostatic capacity is also low even at a low yield. When the pretreatment NaOH addition amount was small (Comparative Example 2), the yield was high, but the electrostatic capacity was not sufficient. When the addition amount of NaOH was too much (Comparative Example 3), the electrostatic capacity was sufficient but the yield was low Able to know. On the other hand, in Examples 1 and 2 according to the method of the present invention, both the yield and the electrostatic capacity showed excellent results.

Comparative Example  4

200 parts by weight of NaOH was added to 100 parts by weight of coal pitch and cooled by heating to 250 DEG C and 150 parts by weight of NaOH was further added to the heat treatment mixture and activated at 900 DEG C by a conventional method to produce activated carbon Respectively. The yield and the electrostatic capacity of the activated carbon were measured. The results are shown in Table 2 below.

Example  3

200 parts by weight of NaOH was added to 100 parts by weight of coal pitch, and the mixture was heated to 500 DEG C and cooled. Then, 150 parts by weight of NaOH was further added to the heat treatment mixture and activated at 900 DEG C by a conventional method to produce activated carbon Respectively. The yield and the electrostatic capacity of the activated carbon were measured. The results are shown in Table 2 below.

Comparative Example  5

200 parts by weight of NaOH was added to 100 parts by weight of coal pitch, and the mixture was heated to 550 DEG C and cooled. Then, 150 parts by weight of NaOH was further added to the heat treatment mixture and activated at 900 DEG C by a conventional method to produce activated carbon Respectively. The yield and the electrostatic capacity of the activated carbon were measured. The results are shown in Table 2 below.

Pretreatment NaOH
Additional added amount
(Parts by weight) yield
(%) Capacitance
(F / cc) NaOH
(Parts by weight) Temperature
(° C) Comparative Example 4
200 250
150 70.2 55.1 Example 3 500 67.1 67.5 Comparative Example 5 550 65.5 66.4

As shown in Table 2, when the pretreatment temperature was low (Comparative Example 4), the yield was high, but the electrostatic capacity was insufficient. When the pretreatment temperature was high (Comparative Example 5), the yield and the electrostatic capacity were excellent. However, in comparison with Example 3 according to the method of the present invention, it can be seen that there is no additional effect due to the increase in the temperature of the pretreatment temperature.

Example  4

100 parts by weight of NaOH was added to 100 parts by weight of coal pitch, and the mixture was heated to 400 DEG C and cooled. Then, 400 parts by weight of NaOH was further added to the heat treatment mixture and activated at 900 DEG C by a conventional method to produce activated carbon . The yield and the electrostatic capacity of the activated carbon were measured. The results are shown in Table 3 below.

Comparative Example  6

100 parts by weight of NaOH was added to 100 parts by weight of coal pitch, and the mixture was heated to 400 DEG C and cooled. Then, 500 parts by weight of NaOH was further added to the heat treatment mixture and activated at 900 DEG C by a conventional method to produce activated carbon . The yield and the electrostatic capacity of the activated carbon were measured. The results are shown in Table 3 below.

Pretreatment NaOH
Additional added amount
(Parts by weight) yield
(%) Capacitance
(F / cc) NaOH addition amount
(Parts by weight) Temperature
(° C) Example 4 100 400 400 62.1 67.4 Comparative Example 6 500 55.6 63.6

As shown in Table 3, when the amount of the post-treated NaOH added is more than 400 parts by weight (Comparative Example 6), the yield decreases and further improvement in the electrostatic capacity can not be expected. On the other hand, in Example 4 according to the method of the present invention, both the yield and the electrostatic capacity showed excellent results.

Claims (2)

Adding 100 parts by weight to 200 parts by weight of an alkali salt to 100 parts by weight of the carbon raw material to obtain a mixture of the carbon raw material and the alkali salt; Heat-treating the mixture at 300 ° C to 500 ° C to melt the alkali salt in the mixture; And Adding 100 parts by weight to 400 parts by weight of an alkali salt to 100 parts by weight of the heat-treated mixture to activate the mixture; Wherein the carbon source is pre-treated. The method according to claim 1, wherein the carbon raw material is a coal-based, petroleum-based or wood-based carbon raw material.