WO1980001683A1

WO1980001683A1 - Process for producing high-density,high-strength carbon and graphite material

Info

Publication number: WO1980001683A1
Application number: PCT/JP1980/000018
Authority: WO
Inventors: H Fukuda; M Nakagawa; S Okada; H Morijiri; K Ozaki
Original assignee: Maruzen Petrochem Co Ltd; H Fukuda; M Nakagawa; S Okada; H Morijiri; K Ozaki
Priority date: 1979-02-09
Filing date: 1980-02-08
Publication date: 1980-08-21
Also published as: DE3034359A1; JPS5725484B2; DE3034359C2; JPS55109214A

Abstract

A process for producing high-density, high-strength carbon material and graphite material from raw coke. Raw coke finely pulverised product alone, or in combination with a binder pitch, is press-molded, the resulting molding is subjected to a primary baking at temperatures of 450-700 C which are lower than in prior art, and the baked product is then impregnated with pitch and subjected to secondary baking at elevated temperatures in a conventional manner. The graphite material is produced by graphitizing the carbon material in a conventional manner. The use of highly pure raw petroleum coke having an ash content of 500 ppm as a starting material according to the preferred embodiment without using the binder pitch provides a particularly useful highly pure graphite material for semiconductors and nuclear reactor materials.

Description

Specification

Method for producing high-density high-strength carbon and graphite materials

Technical field

The present invention relates to a method for producing high-density, high-strength carbon and graphite materials using raw coke as a raw material.

Background.

Conventionally, a general carbon material is usually pulverized into coke that has been calcined at 1,200 to 1,500 ° C, and a binder such as bite is added thereto. It is manufactured through a series of processes such as re-crushing, molding, and firing. However, in such a method, a substantial part of the used underpitch, for example, 1Z5 or more, is decomposed and volatilized during firing, and the remaining carbon content is reduced at the firing temperature. Since the carbon material shrinks as the temperature rises, many pores remain in the carbon material after firing, and the carbon material cannot be sufficiently densified, and usually has a bulk density even if it is graphitized; ^ 1.70 to 1.759 It is only possible to obtain something less than / d.

Therefore, in order to obtain a carbon and graphite material with higher density, a molded body once fired (referred to as a primary fired product) 浸漬 immersed in a melting bite under reduced pressure, A method of impregnating and depositing a pitch into carbon and then carbonizing by firing at a temperature of 100 O'G or more at high temperature has been carried out.] ', In general, this firing-impregnation of pitch Repeat! Is required to be returned. The primary baking temperature is determined so that the carbon content derived from the bizoda pitch is sufficiently shrunk and a large amount of the pitch is impregnated in the subsequent pitch impregnation step. Above 750 ° C,

■ BU EAU Usually, 800 or more is required. When producing reactor graphite material, it may be fired at around 1500'C.

In this way, the conventional method is used.] The production of high-density carbon and graphite materials requires several calcinations at a high temperature and repeated bitite impregnation several times. The energy density is uneconomical and the resulting graphite material has a bulk density of at most 1.85 B / d 9] and is sufficiently satisfactory in terms of strength. It is not something that can be done.

Recently, raw coke-carbon materials with specific properties have been used as raw materials, and high-density carbon and graphite materials have been used by utilizing the sinterability of the raw materials without using binders. A new method for producing the same has been developed (see, for example, Japanese Patent Publication No. 5δ-185559, Japanese Patent Publication No. 50-74281). Such a self-sintering method is extremely valuable in practical use because it can omit complicated steps such as mixing of pitcher and impregnation of bitter. However, in the self-sintering method, the bonding between the carbon material fine powders depends on the sintering of the point contact portion between the fine powder particles, regardless of the binder. There are restrictions such as the selection of the raw material carbon material, the manufacturing conditions of the molded body, and the fact that the density is high enough that the expected high strength cannot be obtained. There are also difficult points to improve Oh! ) In addition, higher strength may be required for some applications.

Disclosure of the invention

The purpose of the present invention is usually easily available, such as in a commercial raw mix. Using any raw coke that can be used as a raw material, a carbon and graphite material having a higher strength than the proposed self-sintering method and a conventional method using calcined coke as a raw material can be used. The aim is to provide a method that is simple and easy to manufacture.

Another object of the present invention is to select high-purity raw petroleum coke as raw coke.] 3 Extremely high purity suitable for semiconductors or reactor core materials, etc. It is an object of the present invention to provide a method for economically producing a high-purity graphite material without going through a “high-purification treatment” that was indispensable in the conventional method.

These and other objects, features and advantages of the present invention will be apparent from the description below.

Therefore, generally speaking, the present invention relates to a raw pulverized raw coke that sinters without being melted during firing, or a mixture of the ground pulverized material and the neutral bite. , And press the molded body to 45 Or! A high-density, high-strength carbon material that can be primarily baked at a temperature of up to 700 ° C, then impregnated with pitch under pressure, and then carbonized by high-temperature secondary calcination in a conventional manner. It provides a method for manufacturing.

Further, the present invention provides a method for producing a high-density and high-strength graphite material, which comprises a step of graphitizing the carbon material thus obtained in a conventional manner. '

BEST MODE FOR CARRYING OUT THE INVENTION The raw material used in the present invention may be any raw coke that is sintered without being melted at the time of firing such as commercially available raw petroleum coke or raw pitch coke. Is. Of course, high-purity raw material with few impurities — If carefully treated with grease, it is possible to obtain high quality carbon and graphite materials.

In the present invention, raw raw coke is finely pulverized using a pulverizer such as a grinding method or an impact method. In general, powder having a mean particle size of 20 A or less can be applied, but the effect of the present invention is more remarkable especially when a powder having a mean particle size of 1 O A ′ or less is used.

The thus obtained raw coke fine powder has a self-sintering property, so that a high density and high strength carbon material which is intended by the method of the present invention by blending with a pitch of pitch is used. Can be led to. However, when raw material having a low volatile content, that is, raw coke having a volatile content of about 7% or less is used as a raw material, the self-sintering property of the raw material is small. A small amount of binder pitch should be blended because the compact may be destroyed during the impregnation. Also! ) Even if raw material with high volatile content is used as raw material, a small amount of tin pitch should be blended.] 9) A more homogeneous carbon material can be obtained. . In any case, satisfactory results can be obtained with a much smaller amount of the binder pitch than in the case of using calcined coke as a raw material. In the conventional method using raw material made from suchichu baked rice, the blending amount of binder bite is 100 parts by weight of core, and usually about 25 to 40 parts by weight. On the other hand, in the case of the present invention, about 5 to 15 parts, preferably about 5 to 10 parts, and 100 parts of raw coke raw material in the case of low volatile coke are used. In the case of volatile coke, the amount is about 0 to 部 parts, preferably about 2 to 4 parts.

(O. PI Of course, it will be clear that the amount of binder pitch varies depending on the raw material, particle size, molding pressure and other conditions.

The molded body obtained in this way is subjected to pitch impregnation after the primary firing, and the primary firing temperature is set at 450-

A range of 700 ° C, especially 500 ° G to 500 ° C, is preferred. When the calcination temperature is 70 OtJ or more, no further improvement in the strength of the carbon material due to pitch impregnation is observed, and the strength decreases despite the increase in bitumen impregnation. Show a tendency to. On the other hand, when the temperature is 45 O'C or less, the primary fired body may be broken during the pitch impregnation treatment because the volatile components of the raw coke are not sufficiently decomposed and the bonding force between the particles is weak. ]), How can I prevent the destruction of octopus?] It is not preferable because it requires a long firing time, for example, 48 hours or more.

With conventional pitch impregnation using calcined coke as a raw material, the primary baking temperature needs to be at least 75 ° C or more, and usually 800 ° C or more. It has been said that the higher the height, the more the bitches are sufficiently impregnated, so that a high-density carbon material can be obtained. On the other hand, in the present invention using raw mix, 45 O'C! ~

700 ° C! , Preferably 50 Q ° C! ~ Ό50 ° C, the conventional method] 3 also achieved satisfactory high-strength carbon material by primary firing in a much lower temperature range! ) However, it was completely predictable from conventional pitch impregnation technology and has great industrial significance.

As described above, in the method of the present invention, an extremely high-strength carbon material can be obtained despite the low primary firing temperature.

A (OMPI

Λ The reason for this is not yet clear, but it is considered as follows.

In other words, in the process of firing the compacted raw coke fine powder, the decomposition of the raw coke begins to occur around 550 ° C. The rapid weight loss ends at a temperature of 0 to 0.50 ° 〇. On the other hand, this is the volume shrinkage due to molding sintering D.) It starts gradually from around 450 ° C, which is as high as 100 ° C], and starts from around 500 ° C. It becomes noticeable up to around 0 0. As described above, since there is a temperature difference between the weight loss and the volume contraction in the firing process, the porosity is high at a low temperature around 500 ° C., and the amount of impregnated bite is large. At ό 0 0 Ό or more, the porosity gradually decreases due to shrinkage of the molded product! ), The amount of pitch to be impregnated is reduced. When the temperature exceeds 700 ° C, the amount of bite that is impregnated again increases, but this does not mean that the shrinkage of the whole compact decreases, but the coke particles that compose it This is probably due to the remarkable shrinkage of the pores, which increases the number of pores. However, when the primary firing is carried out at a temperature of 100 ° C. or more, the amount of bitches to be impregnated is large, but the shrinkage of the compact itself during the secondary firing is small. Due to the large shrinkage of the carbon generated from this, pores and defects increase. On the other hand, when the primary firing is performed at a low temperature of 700 ° C. or less, particularly around 50 ° C., the original green compact still hardly shrinks during the secondary firing. However, the coke formed by the decomposition of the impregnated pitch during the secondary firing gradually shrinks as the temperature rises, and this also shrinks. Pitch impregnated

• A ΟΛ ': ΡΙ A The pores also shrink. The reason for this is that the primary fired product at 450 ° C to 700 ° C is a primary fired product at a higher temperature]), although the pitch impregnation amount is small. Rather, it will provide a high-strength carbon material. Furthermore, thermal decomposition of raw coke as a raw material is still incomplete in primary firing at 700 ° G or less, especially around 5D0 ° G! ) Do the molded body itself! Since the organic part remains, the possibility of forming strong bonds with the raw coke fines when the impregnated pitch carbonizes during the secondary firing process cannot be ignored.

As described above, when the raw coke fine powder is subjected to pressure molding and primary baked and then impregnated with bitumen, the primary calcination temperature range that is advantageous for significantly increasing the impregnation effect is as follows. The abrupt change in the volumetric shrinkage of the compact ends. 1) In the low temperature range], especially in the range where the porosity increases due to the temperature difference between thermal decomposition and volumetric shrinkage. It can be said that the thermal decomposition of raw raw coke does not end, leaving a part that is organic.

As the pitch for impregnation, use is made of a coal pitch, an asphalt pitch, "ethylene", a pitch pitch, and the like. It is also possible to use a mixture of dianthus and diluent, such as tar.

The impregnation temperature is low enough that the molten bite 'can penetrate into the pores of the primary fired product, but it is not easily decomposed or volatilized. ] To 250 ° C. If the bite is mostly soluble in the diluent, such as an ethylene bite, dilute it with the diluent and place it around 100 ° G. It can be impregnated at a low temperature.

The high-temperature secondary baking of the primary-baked product thus impregnated and, if necessary, the subsequent graphitization step can be carried out by a conventional method in the prior art. In the present invention, secondary firing is generally ¹ 0 0 0 ^Ό above temperature, divided Gyoru in example 1 2 0 0 ~ 1 4 0 0 ° C a temperature of approximately. Graphitization is usually performed at a temperature of about 240 to 500 O'C, but depending on the intended use of the graphite material, it may be possible to partially graphitize at a lower temperature. You can do it.

According to the present invention, the raw coke is usually used as raw material without using a limited raw coke or a specially treated carbonaceous raw material. The cost is cheap. In addition, carbon and graphite materials with extremely low densities, high oxidation resistance, chemical resistance, and low specific resistance, even at a low primary firing temperature compared to the conventional method, but with a single pitch impregnation treatment. Is obtained.

Particularly, when the method of the present invention is applied to raw petroleum coke of high purity as raw coke as a raw material, extremely high purity is required for semiconductors or reactor core materials. High-purity graphite material suitable for the intended use can be obtained. For the production of conventional high-purity graphite materials,

Inject chlorine, fluorine, or fluoric debris, etc., into a graphitizing furnace of 250 O'C or higher to remove trace impurities such as metal components that constitute ash in carbon materials. It is necessary to carry out a “purification treatment” to vaporize and remove them by converting them into oxides.))

OKSl This was a factor that further increased product costs. On the contrary, according to the present invention, it is necessary to appropriately select raw materials without any need for "high purification treatment".髙髙 It is possible to obtain very pure graphite material very economically.

A preferred embodiment of the present invention for producing a high-purity graphite material is to pulverize a high-purity raw petroleum coke having an ash content of 500 ppm or less, and to use this as a binder. Press molding without compounding and press the molded body at 450 ° C! Low temperature at a temperature of up to 700 ° G-next firing, then impregnated with high-purity pitch under pressure, high temperature secondary at over 1200 ° C, preferably over 150 ° C Baking, and baking the same fired body. High-purity crude petroleum oil with an ash content of 500 ppm or less

— It is a process of calcining and finely pulverizing the crust to fill it with flour and graphitizing it in the usual way. According to this method, the ash content is 2 (less than about 3 ppm, the boron content is about 0.1 to about 2 ppm, and the purity of high-purity, high-density, high-strength graphite material is about 2 ppm). And can be manufactured economically.

A high-purity crude petroleum coke with an ash content of 500 ppm or less, which is useful as a raw material for this purpose, for example, when cracking ethylene such as naphtha and kerosene oil Prolonged co-treatment of petroleum heavy oil containing very few impurities other than hydrocarbons, such as pyrolysis tar (hereinafter referred to as “ethylene”), as a by-product The crude petroleum coss or the heavy oil, which has a large amount of impurities, obtained in this manner is lightly pyrolyzed in advance, and the components rich in the impurities are polycondensed and removed as bits. It is a raw petroleum coke obtained by converting the remaining fraction into a delayed coke.

OiVPI A particularly preferred example of the last-mentioned coke making method is described in US Pat. No. 4,177,155.

In this embodiment of the present invention, in order to produce a high-purity graphite material, the calcined coke used as the impregnating pitch and the packing in the graphitization process is also of high purity. Should be used. As the bite for impregnation, it is particularly preferable to use a pyrolysis tarbit by-produced during the decomposition of ethylen such as naphtha, kerosene oil, etc. Then, it is preferable to use a finely pulverized powder of calcined coke obtained by calcining the same high-purity crude petroleum coke as used as a raw material in this method.

Hereinafter, the present invention will be described in more detail with reference to examples.

Example 1

Volatile content 1 4.7%, quinoline soluble content 1 2.ό%, Ε / C

0.6 to 30 parts of crude petroleum coexisting water, 25 to 30 parts of water was added, and the mixture was pulverized to an average particle size of 0.5 using an edge runner pulverizer. , Press molding with a molding pressure of 1,000, embedding the obtained compact having a diameter of 5 cra and a height of 5 cm in coke powder, and heating at a heating rate of 50 hours. The primary sintering was performed at 400 to 900 ° C.

This primary fired product is placed in a pressure-resistant container containing a coal tar pitch having a softening point of 87 ° G, and gradually heated to 250 ° C under a reduced pressure of 10 to 2 D 丽 Hg. After being heated for 1 hour, it was kept under a pressure of 10 / ^ for 1 hour to impregnate the bite, and then fired with 1400'G in the same manner as in the primary firing (called secondary fired product). . The secondary fired product was further graphitized at 2,400'C. Table 1 shows the physical properties of the secondary fired product and the graphitized product. For comparison, the results of molding and graphitization without pit impregnation and the physical properties of commercial graphitized products are also shown for comparison.

ΟΛ Ρ1

Example 2

The same crude petroleum mixture as in Example 1 was pulverized by the same method to an average particle size of 5.4 A, and this was rubberized under a pressure of 1000 z. Then, a molded body of 17.5 × 10.5 × 4.0 cm was manufactured. After sintering the compact at 550 ° C for 3 hours, it was impregnated with pitch in the same manner as in Example 1, subjected to secondary calcination, and graphitized at 260 ° C ₍ however, primary The heating rate during secondary firing was 7.5 焼成 GZ, and the retention time during pitch impregnation was 5 hours.

Table 2 shows the bulk density and flexural strength of the secondary fired product and the graphitization. For comparison, the results of molding in the same manner as above, firing and graphitizing without impregnating the pitch are also shown as reference examples. Table 2

Example

The same raw petroleum coextruded as in Example 1 was pulverized with an impact pulverizer to an average particle size of 4.5; ". A compact having a diameter of S cm and a height was manufactured by pressure molding at each pressure of 2, 000. This was subjected to primary firing, bite impregnation, secondary firing, and the like as in Example 1. And 2,200 "2, did. However, primary firing was performed at 550 ° C for 5 hours.

Table S shows the physical properties of the secondary fired product and the blackened product.

Example 4

100 parts of crude petroleum coke with a volatile content of 14.5% has a softening point

8 7. 0 parts of a cold tar pitch were added, and the mixture was ground to an average particle size of 4.4 with an edge runner in the presence of 2 to 5 D parts of water. This was subjected to lanless press molding at a pressure of 1,000 Zc ^ to produce a molded body of 17.5 X 10.5 X 4.0 cm.

This molded body was subjected to primary firing, pitch impregnation, secondary firing, and graphitization at 2,500 ° C. in the same manner as in Example 2.

Table 4 shows the physical properties of the secondary fired product and the graphitized product.

UK

_ OWPI W1PO Table 4

Example 5

Raw petroleum coke with a volatile content of 6.8% is averaged in ball mill

Crushed to 4.5 A and softened to 100 parts of this coke powder

After adding 10 parts of a cold tar pitch at 87 ° C, the mixture was mixed uniformly. This mixture was molded, primary fired, bite impregnated, secondary fired and blackened in the same manner as in Example 1. However.

—The next firing is 550. In G, ό time line _ た.

Table 5 shows the physical properties of the graphitized product.

For comparison, the results of the same method as above without the addition of bitches are also shown. Table 5

■ ¾13R hi A hi, oy.pi V. '^ O 6 Example 6

Raw petroleum coke with a volatile content of 14.5% is pulverized to an average particle size of 5.0 A by an dry runner without adding water to an average particle size of 5.5 A, and then to 55 mesh (JIS sieve) or more. After removing the coarse particles, rubber press molding was performed at a pressure of 1000 to produce a molded article having a diameter of 14 CTI and a height of 1 cm. After sintering the molded body at ό0 for 5 hours, place it in a pressure vessel containing a soft-boiler with a softening point of 87 ° C and place it under a reduced pressure of 10 Table gradually up to 500

After heating, hold for 8 hours under 20 Ζα!

0- impregnated. It was secondarily fired in the same manner as in Example 1 and further graphitized at 280 ° G.

Table 2 shows the physical properties of the graphitized product.

Cut a 4 cm cube from this graphitized product! ) The sample was discharged, heated in a 1000 electric furnace for 10 minutes, and immediately put into cold water. A thermal shock resistance test was performed, but no change was observed in the appearance and strength. Example 7- The same method as in Example 5 was used to classify the raw stone oil mixture that had been finely pulverized to an average particle size of 0.1 ^ "by air classification, and the average particle size was 3.9 A with a yield of about 50%.

ΟίήΡΙ ι7 fine powder was obtained. It was subjected to lanpress molding at a pressure of 250 /, and was graphitized through primary firing, pitch impregnation, and secondary firing in the same manner as in Example 5. However, the pitch impregnation time was 12 hours. Table 7 shows the characteristics of the graphitized products.

This graphite material was cut into 2.5 X 2.5 X 5 cm and used as an electrode. An electric discharge machining test was performed. The work material was alloy steel for molds, and the bottom was machined to a depth of 1 to 2 haze. The electrode polarity was set to low polarity (+), low wear conditions, the pulse width and the pause width were set to 5 OA seconds, and the peak current was set to 25 amperes. Electrode length consumption after processing

The machining surface roughness was about 7 (the electrode length consumption was 2.5 to 5.8% for the first-class commercial product, and the machining surface roughness was 8 to 15 mm).

Example 8

The specific gravity obtained by distilling the pyrolysis tar (naphtha ethylene) produced as a by-product during naphtha ethylene decomposition and excluding the boiling point fraction of 250% or less 1.159, Conradon 12.8% of heavy oil with carbon residue of 12.8% in a coke drum at 9 ^ pressure, 44 ° G 24 hours delay coex The crude petroleum coke with a volatile content of 11.9% obtained by subjecting it to steam

Bi

Ο ΡΙ Used as raw raw mix. This was ground with an edge runner for 2 hours, and then passed through a mesh under a mesh (a Japanese standard sieve).

To produce a formed body having a diameter of 12 cm and a height of 1 and was subjected to primary firing at various primary firing temperatures in the range of 400 ° C. to 90 O′C. At that time, the temperature rise of the firing atmosphere is from 15 ° CZ from room temperature to 560 ° C, from 100 ° C to 40 ° C from 56D′C, and from 40D ° C. Ra ό 0 [! In the meantime, the temperature was maintained at the same temperature for a predetermined time after reaching the predetermined temperature. After cooling, remove the sintered body] and discharge at 220 ° C and ZO according to the usual method.

Under a pressure of G, the ethylene bite was impregnated for 8 hours. The ethylene bite is obtained by distilling naphtha ethylene to remove a boiling point fraction of 55 ° C or lower, and has a softening point of 150 ° C ( Ring-and-ball method), with a fixed carbon content of 5 to 5.3%. The bite-impregnated primary fired product was similarly subjected to secondary firing up to 130 O'C. The temperature rise is the same as above when the temperature rises below 40 O'C] 3, 5'0 / h from 400 * 0 to 750'0, and from 75 ° C to 900 ° C In this case, the temperature was kept at 20 ° C, from 900 ° C to 150 ° C, at 50 ° C, and at 15D0 ° 0 for 3 hours. The obtained secondary fired product is filled with the same raw petroleum coke as the raw material in a calcined powder that has been calcined at 150 ° C, and is directly energized in a normal graphite furnace.)) 2 It was graphitized by heating to 800'C. Table 8 shows the relationship between the primary firing temperature and the bitch impregnation rate, and the characteristics of the secondary fired product and the graphitized product. Raw crude oil coke and 550. The impurity content of the graphite material obtained in the experimental example of primary calcination with C and the same Table 9 compares the characteristics of graphite materials with those of typical commercial graphite materials for nuclear reactors and semiconductor manufacturing.

Table 8

Sintering conditions Graphitized product (2800Ό)

^ C-^-S-SL. Secondary firing product

Hinoa s fern

Time ¾

Shino, 11 I "no (t) s ^ s Bulk specific gravity Flexural strength

,

4 0 0 48 At the time of impregnation

Collapse

45 0 4 8 24.2 1.8 1 1.87 47 0

5 0 0 1 2 24.5 1.78 1.8 6 4 9 0

5 5 0 5-2 5.8 1.78 1.8 5 48 0

00 0 5 22.0 "1.77 1.84 4 7 0

05 0 3 2 0.5 "1.7 7 1.84 4 50

7 0 0 5 1 8.5 1.7 6 1.8 5 440

9 00 5 2 5.8 1.72 1.7 8 5 8 0

9

Example 9

Slurry produced by fluid catalytic cracking of turtle oil D Desulfurized clarified oil, excluding solids in one oil, and then distill off 25% O'C or less of volatile matter]? Heavy oil with a specific gravity of 1.09 15, Conrad-don residual carbon content of 0% and a carbon content of 0% of 5% was designated as Coxsig. Pressure applied to a stainless steel tube with an inner diameter of 4 mm and a length of 20 m heated to 30 g

It was sent by G. The liquid residence time in the stainless steel tube was about 250 seconds. The feed oil that has exited the stainless steel pipe is immediately led to a high-temperature flash tower at normal pressure and 450 ° C, and the pitch at the bottom of the tower is allowed to stay for about 10 minutes. Continuously withdrawn from the lower part, heavy oil having a boiling point of 500 0 or more obtained by removing gas and distillate fractions less than the distillate fraction in the distillate fraction from the top is coke. In a drum _, hold at 455'C under 9 ^ 0 pressure for 28 hours to make a delayed coke, and then inject steam at 440'C for 5 hours to generate 9.4 % Of raw oil coke was obtained. The yield was 52.5 weight based on heavy oil.

The obtained crude petroleum coke was pulverized to an average particle size of ό5 with an impact crusher, then crushed with an edge runner for ό0 minutes, and passed through a mesh screen. Forming was performed with 100 <0> ^ to obtain a formed form of 20X12X0CK. This was primarily fired in exactly the same manner as in Example 8, impregnated with the same pitch, secondary fired, and then graphitized. The impregnation amount of the bitite was 21.9 weight based on the primary fired product], and the dimensions of the graphite material were 17.5 × 10.4 × 5.2 cm. The characteristics and impurities of the obtained graphite material The weight is shown in Table 10 Table 10

Example 1 ο

Direct desulfurized oil of 0.52%, specific gravity 0.9188 and residual carbon of 5.9% Conradon was obtained from Middle Eastern mixed crude oil.

4 5 O 'heated inside diameter 4 Haze and C, were fed at a pressure of 4 ^ ZCM ^z G during scan Te emission Les scan pipe length 2 0 m. The residence time in the stainless steel pipe was about 250 seconds. The distillate discharged from the stainless steel tube was immediately led to a flash distillation column at normal pressure and 43 ° C, and 17.8 weight from the bottom of the column as in Example 9. The pit was extracted, and 59.3 weight heavy oil having a boiling point of 550 ° C or more was obtained from the distillate at the top of the tower. Heavy oil was delayed by 18 hours at 9 ^ G pressure and temperature of 460 ° C for 18 hours to obtain a crude petroleum mixture with a volatile content of 14.5% in a yield of 20.8 weight. Was. In this case, steam treatment was not performed. This raw coke is pulverized to an average particle size of 4.4 "with a pulverizer equipped with a classifier, producing 100/0 (by hydrostatic pressure of ^)? The formed body was graphitized through primary calcination, pitch impregnation, and secondary calcination in the same manner as in Examples 8 and 9.

"BUREA

O.MP] 2 δ property and impurity content are shown in Table 11 Table 11

Industrial applicability

The carbonaceous materials (secondary fired products) and graphite materials (graphitized products) produced by the method of the present invention are very high-density and high-strength materials. The same applies to materials, especially sliding parts and electrodes for electrolysis, etc., as well as various materials for machinery, materials for metallurgy such as crucibles, various types of electric discharge machining electrodes, semiconductors, and materials for nuclear reactors. It can be widely used. In particular, high-purity black material with a low ash content is useful as a semiconductor material and a reactor core material requiring strict standard values.

Claims

24 Scope of Claim

1. Finely pulverized raw coke that melts and sinters when firing, or a mixture of a binder and a binder pitch is press-formed and the formed body is 450 ° C Of high-density, high-strength carbon materials that can be primarily baked at a temperature of up to 70 O'C, then impregnated with pitch under pressure, and then carbonized by high-temperature secondary calcination by a conventional method. Production method.

2. The method according to claim 1, wherein the primary firing temperature is from 500 to 500 t).

-10 5. The method according to claim 1 or 2, wherein the secondary firing is performed at a temperature of at least 100 o'c.

4. The blending amount of the underpitch is less than 100 parts by weight of raw coke raw material and less than 15 parts by weight of D-described in any one of claims 1 to 3 the method of. :

15 5. Finely crushed raw coke, which melts and sinters during firing, or a mixture of binder and bite, is subjected to pressure molding, and the compact is 450 t! Primary baking at a temperature of ~ 700 ° C, impregnating the pit under pressure, and then using a conventional method]) High-temperature secondary baking, and further carbonizing the obtained carbon material according to a conventional method])

20 High-density, high-strength graphite material production method.

6. The method according to claim 5, wherein the subsequent firing temperature is from 500 ° C. to 500 ° C.

7. The method according to claim 5, wherein the secondary firing is performed at least at a temperature of T000 ° C.

5 8. The blending amount of the nodular bite is raw coke raw material 100 The method according to any one of claims 5 to 7, wherein the amount is not more than 15 parts by weight.

9. The method according to any one of claims 5 to 8, wherein the graphite is performed at a temperature of 240 ° C to 500 ° C.

5 10. High-purity crude petroleum coke with an ash content of 500 ppm or less is finely pulverized and press-molded with a binder bite to form a compact. 4 5 O'C! Primary calcination at a temperature of ~ 700 "Ό, then impregnation with high-purity pitch under pressure, high-temperature secondary calcination at 1200 ° C or higher, and the same ash content of the fired body 5 0 0 "Manufacture of high-purity graphite material that can be calcined and pulverized from high-purity petroleum coke of 10 ppm or less and pulverized into fine powder in a conventional manner. Method.

11. The method according to claim 10, wherein the primary firing temperature is from 500 ° to -050. :

15 12. The method according to claim 10 or 11, wherein the secondary firing is performed at a temperature of 150 ° C. or higher.

5. The method according to any one of claims 10 to 12, wherein the graphite is performed at a temperature of 240 ° C. to 500 ° C. 0 °.

14. A high-density 20-degree high-strength carbon material produced by the method according to claim 1.

5. A high-density, high-strength graphite material produced by the method according to claim 5.

16. A high-purity graphite material produced by the method according to claim 10.

VA, WiPO