KR20170105151A - Method Of Needle cokes through a 2-stage pressure heat treatment - Google Patents

Abstract

The present invention relates to a manufacturing method of an excellent needle coke with a yield increased about 10 to 20% through two stages of heat treatment using coal tar, and to the coke manufactured by the method. The needle coke manufactured according to the present invention has a fine structure and is excellent in airtightness, and therefore is suitable for the use in solar cells, secondary batteries, supercapacitor electrode materials, and electrodes.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of manufacturing an acicular coke using two-

The present invention relates to a method for producing an acicular coke, and more particularly, to a method for producing acicular cokes by using a coal tar as a starting material in a 1-stage heat treatment and a 2-stage heat treatment Lt; RTI ID = 0.0 > coke. ≪ / RTI >

Coal cokes are manufactured using coal tar as an intermediate raw material of artificial graphite. Coal tar, the raw material of coal-based coke, is produced in Korea at over 800,000 tons per year. Coal coke is a carbon material of good quality and widely used industrially in semiconductors, light emitting diodes, solar cells, supercapacitors used in automobile batteries, anode materials of secondary batteries, and electrodes. However, due to the lack of carbon-related industries, Korea has been reluctant to import high value-added artificial graphite raw materials due to lack of original technology and production base.

Coke, which is a starting material of carbon materials, is heat treated at 400 to 600 ° C and polymerized by polycondensation and removed by volatilization. The coke is divided into anisotropic and isotropic depending on the surface texture. Typical anisotropic needle cokes are used as the electrode main material of ultra-high power furnace (UHP) with electric capacity of 300 ~ 450kw / ton. The electrode thus manufactured has a low thermal expansion coefficient due to a low thermal expansion due to a temperature gradient because of its high thermal conductivity and low thermal expansion coefficient. Isotropic coke is used as a mechanical bearing material and a carbon material for machine because it has high mechanical and friction stability and has a tight structure due to its compact structure.

Generally, artificial graphite has a complicated manufacturing process in which graphite is formed by mixing compacted coke as a binder and pitch, and then densifying and densifying the molded product by repeating impregnation and firing. The mechanical properties are significantly reduced due to the degassing of the micropores and volatile components during the firing process. This is a fatal disadvantage which slows the rate of temperature rise of the firing and repeats the impregnation, which makes a long-term manufacturing period necessary.

An improved coke production method that shortens such a production time includes a method of inducing self-sintering without using a binder, a method using a modified pitch, a method using a meso-carbon microbead (MCMB), and the like. Thereby improving the internal structure and physical properties in a short time.

Edwards L, Vogt F, Robinette M, Love Ric, Ross A, McClung M, Roush RJ, Morgan W. USE OF SHOT COKE AS AN ANODE RAW MATERIAL. TMS Light Metals, 985-990 (2009). Youm HN, Chang JS, Lee JM, Chung YJ. Structural Changes During the Calcination of Raw Coke. Journal of the Korean Ceramic Society, 29, 10, 773 (1992). Moskalev IV, Kiselkow DM, Strelnikov VN, Valtsifer VA, Petrovykh AP, Petrov AV, Beilina NY. Production of Isotropic Coke in Industrial Trials. Coke and Chemistry, 57, 202-207 (2014).

In view of the above problems of the prior art, the present invention has been made to solve the above-mentioned problems of the prior art by providing a coke oven which is capable of increasing the yield of coke by about 10 to 20% It is an object of the present invention to provide a method for producing an acicular coke through a short heat treatment, and an acicular coke having improved surface texture characteristics and physical properties produced using the acicular coke.

In order to accomplish the above object, the present invention provides a method for producing a coal tar, A first step of performing a heat treatment at a temperature of 300 ° C to 400 ° C for 1 hour to 5 hours; And a second step of flowing an inert gas at a temperature of 400 ° C to 500 ° C for 1 hour to 5 hours.

The present invention also provides an acicular coke produced by the process according to the present invention.

In addition, the present invention relates to a coal tar supply unit; A first combustion unit connected to the supply unit and performing a first heat treatment in a vacuum state at a temperature of 300 ° C to 400 ° C for 1 hour to 5 hours; And a second combustion unit connected to the first combustion unit to supply an inert gas and performing a secondary heat treatment at a temperature of 400 ° C to 500 ° C for 1 hour to 5 hours; The present invention also provides an apparatus for producing an acicular coke.

In the case of producing the acicular coke using the two-stage heat treatment of the present invention, the molecular weight of the coal tar is controlled to be optimized through the primary heat treatment, and the QI is increased by 0.1 to 1% and the TI is increased by 2 to 5% It is possible to manufacture coal tar with an increased amount of Beta resin and convert the coal tar into cokes through secondary heat treatment to control the volatile content to about 20%.

Accordingly, the yield of the coke is increased by about 10 to 20%, and an acicular coke having improved surface texture characteristics and physical properties can be obtained.

FIG. 1 is a photograph showing the insolubility of raw materials into quinoline, tetrahydrofuran, toluene, benzene and hexane. FIG. 1 is a photograph showing the insolubility of raw materials into quinoline, tetrahydrofuran, toluene, benzene and hexane.
2 is a photograph showing a device for manufacturing delayed cokes.
1 is a reactor; 2 is an electric heater; 3 is a pressure gauge; 4 is stirring; 5 is a temperature and stirring system; 6 is a thermocouple; 7 is a nitrogen (N2 ₎ gas system; 8 is a reaction-gas outlet; 9 is a store for heavy distillates; 10 is an absorber;
3 is a photograph showing the manufacturing apparatus.
11 is a reactor; 12 is an electric heater; 13 is a pressure gauge; 14 is a stirring; 15 is a temperature and stirring system; 16 is a thermocouple; 17 is a reaction-gas outlet; 18 is a gas valve; 19 is a water trap;
FIG. 4 (a) is a photograph showing the effect of the reaction time on the QI and TI according to the change of the 1-stage reaction temperature while fixing the reaction time to 3 hours. FIG. 4 (b) And QI and TI according to the reaction time.
Figure 5 is a photograph of Beta resin at 1-stage temperature for 1 hour and 3 hours of ARCT.
FIG. 6 is a photograph of a MALDI-TOF mass spectra using RCT and α-Cyano-4-hydroxycinnamic acid of ARCT as a matrix.
FIG. 7 is a TGA-curves analysis photograph of DCS and ADCS. FIG. 7A is a TGA-curves photograph of the DCS according to the delayed coking time and temperature, (c) and (d) are TGA-curves photographs with time and temperature of ADCS.
FIG. 8 is a polarized microscope photograph of nine samples according to the temperature and time of DCS. (b) 400 DEG C for 2 hours; (c) 400 DEG C for 3 hours; (d) 450 DEG C for 1 hour; (e) 450 DEG C for 2 hours; (f) 450 DEG C for 3 hours; (g) 500 DEG C 1 hr; (h) 500 DEG C for 2 hours; (i) analysis at 500 DEG C for 3 hours.
FIG. 9 is a polarizing microscope photograph of nine samples according to the ADCS autoclave and delayed coking temperature and time. FIG. 9 shows (a) A300 ° C 1hr-D450 ° C 1hr; (b) A300 DEG C 1hr-D450 DEG C 2hr; (c) A300 ° C 1hr-D500 ° C 1hr; (d) A330 ° C 1hr-D450 ° C 1hr; (e) A330 ° C 1hr-D450 ° C 2hr; (f) A330 ° C 1hr-D500 ° C 1hr; (g) A360 DEG C 1hr-D450 DEG C 1hr; (h) A360 ° C 1hr-D450 ° C 2hr; (i) An analysis at a temperature of A360 DEG C for 1 hour and D500 DEG C for 1 hour.
10 is a photograph showing the effect of the caulking yield according to the two-step process.

Hereinafter, the present invention will be described in detail. In the following description of the present invention, a detailed description of known configurations and functions will be omitted.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and should be construed in accordance with the technical meanings and concepts of the present invention.

The embodiments described in the present specification and the configurations shown in the drawings are preferred embodiments of the present invention and are not intended to represent all of the technical ideas of the present invention and thus various equivalents and modifications Can be.

The present invention relates to a method for producing Coal tar, which comprises a first step of heat treating a coal tar in a vacuum state at a temperature of 300 ° C to 400 ° C for 1 hour to 5 hours; And a second step of flowing an inert gas at a temperature of 400 ° C to 500 ° C for 1 hour to 5 hours.

When the temperature in the first step is below the lower limit of the above range, there is a problem that the pressure is controlled to 10 kgf / cm ² or less and the molecular weight is smaller than the optimal molecular weight. In the case of exceeding the upper limit of the above range, Is increased to not less than 20 kgf / cm ² and is controlled to a molecular weight greater than the optimal molecular weight, resulting in a small molecular weight in an abnormal range, which is undesirable.

When the heat treatment time in the first step is below the lower limit of the above range, there is a problem that the molecular weight is adjusted to be less than the optimal molecular weight. When the upper limit of the above range is exceeded, It is undesirable because a problem occurs.

When the temperature in the second step is below the lower limit of the above range, there is a problem that a pitch other than the coke can be produced. In the case where the temperature exceeds the upper limit of the above range, the volatile content is extremely reduced, Which causes a phenomenon of swelling in a later process, which is not preferable.

If the heat treatment time in the second step is below the lower limit of the above range, there is a problem that a pitch other than the coke can be produced. If the heat treatment time exceeds the upper limit of the above range, the volatile content is extremely reduced, A problem such as a phenomenon of swelling in a later process is caused, which is not preferable.

The vacuum state of the first step preferably has a pressure of 10 kgf / cm ² to 20 kgf / cm ² .

There is a problem that when the pressure is below the lower limit of the above range, the molecular weight distribution is adjusted to a molecular weight distribution smaller than the optimum molecular weight. When the upper limit of the above range is exceeded, Which is undesirable.

The inert gas in the second step may be composed of at least one element selected from the group consisting of nitrogen and elements of Group 18 consisting of argon, helium, neon, krypton, xenon, and radon.

The flow rate of the inert gas in the second step is preferably 0.3 L / min to 0.6 L / min based on 60 g of coal tar.

In the first step, the yield of the molecular weight of the coal tar is increased, and the proper molecular weight of the acicular cokes can be controlled.

In the first step, the quinoline insoluble QI of the coal tar can be increased by 0.1 to 1%, and the toluene insoluble (TI) may be increased by 2 to 5%.

The second step may adjust the volatile content of the coke to 0 to 20%.

Also provided is an acicular coke produced by the process of claim 1.

Also, a supply part of coal tar (coal tar); A first combustion unit connected to the supply unit and performing a first heat treatment in a vacuum state at a temperature of 300 ° C to 400 ° C for 1 hour to 5 hours; And a second combustion unit connected to the first combustion unit to supply an inert gas and performing a secondary heat treatment at a temperature of 400 ° C to 500 ° C for 1 hour to 5 hours; The present invention also provides an apparatus for producing an acicular coke.

And a device connected to the first combustion unit to adjust the pressure.

The apparatus may further include a temperature and time controller connected to the first combustion unit and the second combustion unit, respectively.

And a discharge pipe connected to the first combustion unit and the second combustion unit to discharge gas.

Hereinafter, the present invention will be described in more detail with reference to Examples. It is to be understood by those skilled in the art that these embodiments are only for describing the present invention in more detail and that the scope of the present invention is not limited by these embodiments in accordance with the gist of the present invention .

Example  One

The basic raw material used in this experiment is coal tar produced by Company P. The raw material is mixed with tetrahydrofuran (THF) at a ratio of 1: 1 for about 5 minutes, Were used for the experiment.

Table 1 shows the elemental analysis (EA), quinoline insoluble (QI), and toluene insoluble (TI) of purified coal tar (Coal tar). Elemental analysis (wt%) Insolubility (%) C H N S TI QI beta -resin 91.77 5.74 1.75 0.64 8.50 - 5.65

(RCT) purified by Tetrahydrofuran (THF) was added to an autoclave process using the apparatus of FIG. 2 to prepare six kinds of coal tar (ARCT) having different physical properties. At this time, autoclave (RCT) The reaction temperature of the process was 300 ° C, 330 ° C and 360 ° C, and the time was 1hr and 3hr. The temperature rise time was 10 ° C / min and the stirring speed was 60rpm.

The six ARCTs thus prepared were subjected to a total of 18 diluted coke samples (ADCS) at 450 DEG C for 1 hour, 450 DEG C for 2 hours, and 500 DEG C for 1 hour using a Delayed Cokes device of FIG. )).

Comparative Example  One

The mixture was thoroughly mixed with tetrahydrofuran (THF) at a ratio of 1: 1 for about 5 minutes and then diluted cokes (Delayed Cokes) were obtained by using the apparatus shown in FIG. 1 using refined coke (RCT) ) .

The fixed conditions in this experiment are a stirring speed of 70 rpm, a nitrogen (N ₂₎ gas purging rate of 0.4 L / min, and a heating rate of 10 ° C./min. Under this fixed condition, the temperature was changed from 400 ° C to 500 ° C, and the reaction time was changed from 1 hr to 3 hr to make a total of 9 Delayed Cokes Samples (DCS).

Evaluation example 1 - Autoclave  Temperature dependent QI / TI  Physical property experiment

Figs. 3 to 5 show the influence of changes in the autoclave process on QI and TI of RCT and ARCT. FIG. 3 shows the effect of changes in the autoclave temperature on QI and TI. As a result of the addition of the autoclave process, the QI was increased by about 0.5%, and the autoclave reaction temperature was 300 ° C. 0.0 > 0.03%. ≪ / RTI > In contrast, TI increased gradually with autoclave temperature, increasing the Beta resin by up to 14%. Due to the autoclave process, molecules with very large molecular weights were decomposed into low molecular weight, and RCT, which is a low - molecular weight polymer, undergoes a condensation polymerization reaction, so that TI is significantly increased but QI is increased to a small amount.

FIG. 4 shows the effect of changes in the autoclave reaction time and temperature on QI and TI. FIG. 4 (a) shows the increase in QI and TI with increasing temperature, FIG. 4 The increase in QI and TI can be confirmed.

FIG. 5 shows the effect of changes in autoclave reaction time and temperature on the beta resin. As the reaction time and temperature increase, it is confirmed that the beta resin increased.

Figure 6 demonstrates that ARCT is up-normalized in molecular weight over RCT.

Evaluation example 2 - DSC  And ADCS TGA -curve( TGA -curve) experiment

Figure 7 shows the TGA-curve of DCS and ADCS according to delayed coking conditions.

(a) shows the TGA curve of the DCS, which shows that the weight loss decreases with increasing delayed coking temperature and reaction time. It can be confirmed that there is no swelling in the carbonization process from 450 DEG C for 1 hour to 500 DEG C for 3 hours in which the weight reduction is about 15% or less.

 (b), (c), and (d), the TGA 900 ° C residual was increased with the increase of the autoclave temperature, but the decrease was observed at 360 ° C. As shown in FIG. 4, this phenomenon is caused by a process in which an RCT molecule having a very large molecular weight is decomposed by an autoclave.

Evaluation example 3 - DSC  And ADCS  Polarization Microscopy Analysis

Figure 8 shows a polarization microscopy analysis of nine samples of DCS. 8 (a) and 8 (b) show the isotropic coke as a step of forming a mesophase. However, in FIG. 7 (a), the TGA 900 ° C volatile content at 400 ° C. for 1 hour and 400 ° C. for 2 hours is about 30% It is difficult to fabricate an isotropic coke as a simple delayed coking device. The coke at 450 ℃ showed anisotropy in the form of perfect mesophase, and the coke at 500 ℃ showed clearness as the delayed coking reaction time increased.

FIG. 9 shows a polarization microscope analysis of an ADCS with an autoclave added. The ADCS treated with an autoclave at 300 ° C and 330 ° C showed no difference from DCS. (G), (h) and (i) of FIG. 9 in which the molecular weight distribution is leveled upward and the volatile content is slightly increased in the vicinity of the autoclave 360 ° C as shown in the results of FIG. 6 and FIG. 7, The structure of the coke was shown. On the other hand, FIG. 8 (i) and FIG. 9 (g) show the same level of acicular coke, so that the temperature range in which the acicular coke can be obtained is increased by adding an autoclave process have.

Evaluation example 4 - Yield  Confirm

Fig. 10 shows the change of the yield according to the autoclave temperature. Compared with non-autoclave, it can be seen that the yield was increased by about 14%. It was confirmed that the yield of the autoclave 360 ° C was reduced again because a very large molecular weight was decomposed and vaporized as volatile components.

As described above, preferred embodiments of the present invention have been disclosed in the present specification and drawings, and although specific terms have been used, they have been used only in a general sense to easily describe the technical contents of the present invention and to facilitate understanding of the invention , And are not intended to limit the scope of the present invention.

It is to be understood by those skilled in the art that other modifications based on the technical idea of the present invention are possible in addition to the embodiments disclosed herein.

Claims (12)

A first step of heat treating the coal tar in a vacuum state at a temperature of 300 ° C to 400 ° C for 1 hour to 5 hours; And
And a second step of flowing an inert gas and performing heat treatment at a temperature of 400 ° C to 500 ° C for 1 hour to 5 hours.
A method for producing an acicular coke.
The method according to claim 1,
Wherein the vacuum state of the first step is a pressure of 10 kgf / cm ² to 20 kgf / cm ² .
The method according to claim 1,
Wherein the inert gas in the second step is at least one member selected from the group consisting of nitrogen and elements of Group 18 consisting of argon, helium, neon, krypton, xenon, and radon.
The method according to claim 1,
Wherein the flow rate of the inert gas in the second step is 0.3 L / min to 0.6 L / min based on 60 g of coal tar.
The method according to claim 1,
Wherein the first step is to increase the molecular weight of the coal tar and to control the molecular weight of the acicular cokes to an appropriate molecular weight.
The method according to claim 1,
The first step is characterized in that quinoline insoluble (QI) of the coal tar is increased by 0.1 to 1% and the toluene insoluble (TI) is increased by 2 to 5% to increase the betaine resin By weight based on the weight of the coke.
The method according to claim 1,
Wherein the second step is to adjust the volatile content of the coke to 0 to 20% or less.
An acicular coke produced by the method of claim 1.
A supplier of coal tar;
And is connected to the supply part and is maintained at a temperature of 300 ° C to 400 ° C for 1 hour to 5 hours A first combustion section for performing a first heat treatment for a predetermined time; And
A second combustion unit connected to the first combustion unit to supply an inert gas and performing a secondary heat treatment at a temperature of 400 ° C to 500 ° C for 1 hour to 5 hours;
Wherein the coke-like coke is produced by the method.
10. The method of claim 9,
Further comprising a device connected to the first combustion unit to adjust the pressure.
10. The method of claim 9,
Further comprising a device connected to the first combustion part and the second combustion part to adjust temperature and time.
10. The method of claim 9,
Further comprising a discharge pipe connected to the first combustion unit and the second combustion unit to discharge gas.

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