JPS59215387A - Preparation of pitch - Google Patents

Abstract

PURPOSE:To prepare a high-quality pitch having an excellent carbonizing property, with a good yield, by hydrogenating a tri-penta-cyclic aromatic compd., followed by oxidation. CONSTITUTION:A tri-penta-cyclic aromatic compd. or a mixt. of at least two of the compd. is lightly hydrogenated to such an extent that aliphatic hydrogen specified by (Halpha+Hbeta+Hgamma) (where Ha is 6-10ppm; Halpha is 1-2ppm; Hbeta is 2- 4ppm; Hgamma is 0.3-1.1ppm) may be 35-70% in proton NMR and no decomposition of raw material may take place. The hydrogenated raw material is then oxidized by air blowing until aliphatic hydrogen (Halpha+Hbeta+Hgamma) remaining in the resultant pitch may be in 15-35%.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing pitch, and more particularly to a method for producing high-quality pitch, which is particularly suitable as a raw material for carbon materials, at a high yield.

carbon e! Several methods are known for producing raw material pitch for carbon materials such as i-navy. For example, there is a method of heat-treating petroleum-based or coal-tar-based pitch to obtain mesophase pitch. However, this method has
Various problems exist: the raw materials are a mixture of countless reactive chemical species, which makes reaction design difficult in terms of setup and operating conditions; However, high-quality mesophase pitch cannot be produced because poor quality mesophase is mixed in; especially when coal tar-based bits are used as a raw material, a step to remove impurities is required; the produced mesophase pitch is Due to its poor fluidity, it has poor spinnability and moldability (compressibility) when producing carbon fibers; it also shows that it is of poor quality as a carbon material when observed under a microscope during carbonization during the production of carbon materials. In some cases, it appears as a fine mosaic. Furthermore, the method of producing mesoface pitch by thermally decomposing and polycondensing a liquid hydrocarbon mixture has drawbacks such as a low pitch yield and the quality of mesoface pitch not necessarily being satisfactory. be.

The present inventor has conducted various studies while keeping in mind the problems of the conventional methods as described above, and as a result, the present inventors have discovered that
We have discovered that high-quality pitch with excellent carbonization properties can be collected in a high yield by introducing hydrogen into the aromatic ring at a specific ratio and then subjecting it to near-blowing treatment under heating. The present invention was completed based on this new knowledge.

It is generally known that aliphatic hydrogen introduced into the pitch reduces the carbonization yield, while near-blowing the hip under heating improves the carbonization yield of the pitch, but may also deteriorate the carbonization properties. Are known. However, according to the method of the present invention in which hydrogen is added at a specific ratio and then near blowing is performed, an unexpected effect is achieved in that the carbonization yield of the starting material can be improved and the carbonization characteristics can be improved at the same time.

The starting material of the present invention is a coal-based heavy distillate containing at least 8,096 or more 3- to 5-ring aromatic compounds.

Examples of these aromatic compounds include an-1-helacene derivatives such as an-I-hracene and methylanthracene; phenan-1-lene-11 groups such as phenanthrene and methylphenanthrene; fluoranthene derivatives such as fluoranthene and methylfluoranthene; pyrene and methylpyrene. Pyrene derivatives such as benzophenanthrene and its methyl m
39 compounds; Oxygen-containing aromatic compounds such as dibenzofuran, diphenylene oxide, and methyldiphenylene oxide; Examples include nitrogen-containing aromatic compounds such as quinoline and carbazole.

In the present invention, the starting material 1 as described above is first subjected to a slight hydrogenation treatment. Although the method of hydrogenation treatment is not particularly limited, the degree of hydrogenation is important. That is, 101-n N M
aliphatic hydrogen (1') defined as below in H
Hydrogenation is carried out to such an extent that α+Hβ+Hγ) is 35 to 7096 and the raw material is not decomposed.

Ha: 6 to 10 ppm,! -1a: 1.1~2p
p.m.

+1! 3: 2 to 4 ppm, 17: Q, 3 to 1. it) 11m
Hydrogenation methods include, for example, Ni-~1O-AQ203
system, in the presence of a catalyst such as Co-Mo-AQ203 system, hydrogen pressure 20-200 kg/Cm2, temperature 350-440°C
For example, catalytic hydrogenation can be carried out under conditions of about 0.3 to 2 cycles. Alternatively, birch reduction (normal pressure, 100-120
C. for 1 to 2 hours).

The hydrogenated starting material is then air blown.
1 oxidize. The oxidation is the residual aliphatic hydrogen (Hα + Hβ + H
The process is continued until the ratio of 15% to 35%, preferably 20% to 30%. The conditions during the oxidation treatment are not particularly limited, but usually under normal pressure, 150-350°C, 1-40°C.
Time, ventilation ω test r! 0.5-10m per l-1g! 2/
It should be about seconds. Furthermore, when the treatment temperature is higher than the boiling point of the substance to be oxidized, it is preferable to oxidize under pressure or reflux.

According to one method of the present invention, mesoface pitch of crow quality can be produced in high yield without any difficulty in terms of equipment or operating conditions.
1 will be given. 1q mesoface pitch has good fluidity and has excellent spinnability and moldability when used, for example, in the production of charcoal fibers.In addition, it is an excellent carbon material when carbonized. There is also an optical flow texture, which is said to exhibit similar properties.
).

Example 1 Heavy anthracene oil (distillate oil from tar distillation containing anthracene, phenanthrene, acenaphthene, pyrene, etc. as main components, Hα+Hβ+Hγ=17%) was converted into Ni-MO
-H2 initial pressure 100 kg/' in the presence of AQ203 catalyst
Hydrogenation treatment was carried out using Cl112 at a temperature of 380° C. for 2 hours. Thus, Hα + 1β 10H of heavy anthralene oil is,
J1 was added to 35%.

Next, the hydrogenated heavy anthrahine oil was near-blown at 220° C. for 24 hours. The air suction rate was 2 mQ/sec per q of hydrogenated heavy anthracene oil.

The product after near blowing is distilled under reduced pressure to a boiling point of 350
Pitch was obtained with a yield of 57% by removing light components below .degree. The aliphatic hydrogen content of this pitch is 15%,
A polymer component having a molecular weight of m1ooo or more was also produced.

In order to express the carbonization properties of the pitch obtained in this example in mg,
A sample was placed in a heat-resistant glass container having a diameter of 301 mm and a length of 300 mm, pressed in a nitrogen gas stream to 600° C. for 1 hour, and then held at the same temperature for 2 hours to carbonize. The carbonization yield, defined below, was 28%.

Residual carbide m (a) Carbonization yield - The carbide having a pitch of 1!I in this example shows an optical flow pattern.

Comparative Example 1 Same as Example 1? The carbonization yield was only 3% when charcoal was directly made from 1 to 100 m of helical oil in the same manner as in Example 1.

Furthermore, after embedding the carbide in plastic and polishing the surface, the result of observation with a polarized blind mirror is as shown in Participant Drawing H, indicating the optical flow.

Comparative Example 2 When the same helical oil as in Example 1 was hydrogenated in the same manner as in Example 1 and immediately carbonized, the carbonization yield was almost zero and J3.

Comparative Example 3 The same deuterium 1-helical oil as in Example 1 was subjected to near-blowing treatment, and then the product was reduced by steaming.
(By removing the boiling point below 350℃, the yield was 76.
The pitch is 11%.

The obtained pitch was carbonized in the same manner as in Example 1, and the carbonization yield was 27%.

Also, polish the object in the same manner as in Example 1,
The results of observation using a light microscope showed a fine mosaic shape as shown in the reference drawing (■).

Comparative Example 4 The same hydrogenated Anne I spiral oil as in Example 1 was heated to 280'
Near blowing treatment was performed at C for 15 hours.

Air suction volume is 1 to 2 per hydrogenated oil.
mQ/sec.

The near blowing product is distilled under reduced pressure and has a boiling point of 350.
By removing light components below ℃, the yield was 33%.
Bituat is t=. Book, tchi (7) IIRtl/j
(Hydrogen was only 2%.

When the above pitch was carbonized in the same manner as in Example 1,
The carbonization yield was 56%.

Further, the carbide was polished in the same manner as in Example 1 and observed under a light microscope. As shown in Reference Drawing IV, it had a fine mosaic shape.

Example 2 420 mQ of ethylenediamine was added to 50 g of the same heavy anthracene oil as in Example 1, and 1115 g was added little by little while stirring at 90 to 95° C., and stirring was continued for an additional 20 hours. After neutralizing the reaction product with hydrochloric acid, bembin was added to recover hydrogenated anthracene oil. The aliphatic hydrogen content of the anthracene oil for hydrogenation reached 60%.

Next, the An1 to spiral oil for hydrogenation was subjected to near blowing treatment in the same manner as in Example 1, and then the product was distilled under reduced pressure to remove light components with a boiling point of 350° C. or lower to produce pitch with a yield of 68%. I got it. The aliphatic water blue of this pitch is 3
It was 0%.

When the pitch was carbonized in the same manner as in Example 1, the carbonization yield was 39%.

Also, polarized light microscopy of the obtained carbide! The i-chain photograph is shown in the reference drawing ■93ffi'), and the angle is θ°;
It shows sai, remo, and niu.

(Below) Agent: Patent Attorney Eiji Mitsue

Claims (1)

[Claims] (2) A method for producing bitters, which comprises hydrogenating 1fI of 3 to 50 aromatic compounds or a mixture of two or more thereof, and then oxidizing the mixture.