JPS63221196A - Production of carbon fiber by using as raw material component prepared through pretreatment of component in petroleum pitch - Google Patents

Abstract

PURPOSE:To prepare mesophase pitch capable of providing a carbon fiber having high strength and ultra-high elasticity, by using a lifenate extracted from non- mesopitch prepd. from petroleum pitch. CONSTITUTION:A component having a b.p. range from an initial point of 460 deg.C - an end point of 560 deg.C and prepd. by distilling in vacuo petroleum pitch obtained as a by-product in thermal catalytic cracking of a desulfurized vacuum gas oil to obtain a 85%-cut fraction and extracting the fraction with a 6-8C aliph. hydrocarbon is heated with stirring at 380-420 deg.C for 2-10hr to prepare pitch containing 5-15% mesophase. The pitch is then aged at 300-350 deg.C for 10-40hr in a non-oxidizing gas stream to allow only mesophases to fuse and grow into a large size, and the non-mesopitch free from mesophase pitch is separated from the mesophase pitch. The non-mesopitch is extracted with a 6-8C aliph. hydrocarbon to obtain lifenate. The lifenate is heated at 380-420 deg.C for 2-6hr to prepare pitch containing 20-60% mesophase. Only the mesophases are fused and grown into a large size, followed by separation and recovery thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to a method for producing 100% mesophase pitch with extremely unique physical properties for producing high-strength, ultra-high-modulus carbon fibers, and particularly for producing carbon fibers as fillers for carbon-carbon composites. and for providing the pitch of the matrix.

[Conventional technology]

In recent years, due to the rapid development of the aircraft, automobile, and other transportation manufacturing industries, and the combination with special substances that will become necessary materials for the future space industry, some of their physical properties have become extremely superior. There is a growing desire for materials that can exhibit specificity, and there is a strong demand for materials that have particularly high strength and strong elasticity, and that are lightweight and inexpensive at the same time. Research into reinforced resins to meet these demands is being actively conducted.

One of the most promising materials for use in reinforced resins is long-fiber, high-strength, high-modulus carbon fiber.

This material appeared only at the beginning of the rapid growth of the aforementioned industry, and when combined with resins, it is possible to obtain reinforced resins with properties that are completely unparalleled. . This reinforced resin is currently widely used in sports equipment, fishing equipment, etc., in addition to the above-mentioned industries.

As a method for manufacturing high-strength, high-modulus carbon fibers at low cost, a method for manufacturing high-strength, high-modulus carbon fibers using pitch containing mesophase pitch as a raw material was proposed in Japanese Patent Publication No. 54-1.
It is a known fact that the pitch described in No. 810 and containing mesophase pitch is a raw material for high strength and high modulus carbon fiber. However, pitch containing mesophase pitch contains a large amount of non-mesopitch, and therefore is not considered optimal as a raw material for high-strength, high-modulus carbon fibers.

According to Japanese Patent Publication No. 57-88, 016, the H0 component is about 2.
0% → about 20.0%, B, component about 15.0% - 'about 45. o%, and the remainder is benzene insoluble matter (more than H6
Component and B, the analysis method for the component is considered to be different from the analysis method of this application), and the mesophase pitch is about 90
A method for manufacturing carbon fiber using pitch containing % or more of carbon fiber as a raw material is described. However, according to the description in Japanese Patent Publication No. 57-88,016, the physical properties of the carbon fiber obtained by this method cannot be said to be high strength and high elasticity.

[Problems to be solved by the present invention]

The purpose of the present invention is to provide a method for producing 100% mesophase pitch for producing long-fiber, high-strength, high-modulus carbon fibers. After ripening, the upper layer non-mesopitch is separated into the upper layer non-mesopitch containing no menphase and the lower layer mesophase pitch based on the difference in specific gravity, and the upper layer non-mesopitch is separated into an aliphatic pitch containing 6 to 8 carbon atoms. An object of the present invention is to provide a method for producing IOOS mesophase pitch with excellent physical properties using a raffinate extracted with hydrocarbons as a precursor.

[Means to solve the problem]

The petroleum pitch produced by thermal catalytic cracking (FCC) of desulfurized vacuum gas oil is distilled under reduced pressure and cut by 85% (initial distillation 460°C to final distillation 560°C) (Dffi composition is a H1 component of 20% to 84°C). %, B. component 16q6 to 80%,
The chemical composition and physical properties of the (7) H1 component and B component also differ depending on the type of crude oil and the method of production thereof.

That is, the average molecular weight of the H8 component is 310 to 400, and its softening point is 40°C to 55°C. First, an H. As a component raw material, non-oxidizing gas is blown into it and heated at a temperature of 380° C. to 420° C. for 2 hours to 10 hours under normal pressure or pressure while stirring to produce a pitch containing 5% to 15% of mesophase pitch, This generated pitch is heated at 300°C to 350°C under non-oxidizing gas.
By aging for 0 to 40 hours, only the mesophase pitch in the pitch is fused and becomes gigantic.
．． 0% → 17.0 section, B, component 20.0% → 39.0
%, Q, S, component 42.0% → 66.0%, Q. i.
The non-mesopitch layer (which can be confirmed with a polarizing microscope) is obtained by solvent extraction of aliphatic hydrocarbons as described above. Raffinate (H0 component 0.5% or less, B
, component 22.0% → 44.0%, Q, S, component 51.0
% → 78.0%, Q. i. 0.8 inch or less).

B in non-mesopitch produced by the above pretreatment
This component is completely different in average molecular weight and softening point from the B component in the 85-thick fraction obtained by vacuum distillation of petroleum pitch, which is produced by thermal catalytic cracking (YCC) of desulfurized vacuum gas oil. B. The ingredients have been pre-treated to minimize the influence of the type of crude oil. B. The ingredients have extremely stable physical properties.
o.

It is extremely excellent as a raw material for chimesophase pitch.

Next, the above-mentioned upper layer of non-mesopitch is extracted with a raffinate (carbon number 6 to 8) obtained by solvent extraction of aliphatic hydrocarbons (carbon number 6 to 8).
H1 component 0.5% or less, B component 24.0% 444.0
%, Q. S, component 51.0% → 78.0%, Q. i.
A non-oxidizing gas is blown into it and heated at a temperature of 380°C to 420°C for 2 to 6 hours with stirring, and the mesophase pitch is added to 60%. Pitch is produced, and the produced pitch is aged for 10 to 40 hours under a flow of non-oxidizing gas at a temperature of 300°C to 350°C, and only the mesophase pitch in the pitch is fused to a large size. Non-mesopitch containing no mesophase pitch (H, component 0.
1% or less, B, component 10.0% → 35.0%, Q, S
, component 61.0% → 89.0%, Q. i. component 0.4f
i → 4.0%) and the lower layer 100% mesophase pitch (H, component 0.05 cm or less, B, component 8.0% → 21
．． 0%, Q. S, component 42.0% → 58.0%, Q. i
．． A method is provided for clearly separating the components (28.0% → 45.0%) based on the difference in specific gravity, and refining this 100% meso 7Aze pitch as pitch for melt spinning. The softening point of this pitch for melt spinning is 260'C to 290°C.
It is.

Non-mesopitch (H.

Ingredient sail 5% or less, B, ingredient 24.0% → 44.0%, Q
．． S.

Ingredients 51.0% → 78.0%, Q. i. component 0.8 inch or less), non-mesopitch (H, component 0.1 inch or less, B, component 10.
0% → 35.0%, Q, S, component 61.0% → 87.
0%, Q. i. Mix 60 to 140 parts of 0.4% to 4.0% of mesophase pitch, and add to this mixture approximately 100% of non-mesopitch (H, component) that does not contain any mesophase in the upper layer, which is produced as a by-product when producing mesophase pitch. 0.1 inch or less, B,
Ingredients 1080% → 35.0%, Q. S, component 61.0%
→89.0%, Q. i. Ingredients 0゜4% → 4.0%)
A non-oxidizing gas is blown into the mixture and heated under normal pressure or pressure at a temperature of 380°C to 420°C for 1 to 6 hours with stirring to produce a pitch containing 20% to 60% mesophase pitch. This produced pitch is aged for 10 to 40 hours at a temperature of 300°C to 350°C under a flow of non-oxidizing gas, so that only the mesophase pitch in the pitch is fused and becomes gigantic, and at that aging temperature, the entire mesophase layer in the upper layer is completely removed. Contains non-mesopitch (H, component 0.1% or less, B, component 10.0 → 35.0%, cl, s, component 61.0%
→89.0%, Q, soil, component 0.4% → 4.0%)
and the lower layer 100% mesophase pitch (H, component 0.0
5 inches or less, B, component 8.0% → 2140%, Q. S, component 42. O Chili 58.0%, Q. i, component 28.0%→
45.0%) based on the difference in specific gravity, and this is purified as pitch for melt spinning.

Each component of this Zoo% Men 7A's pitch, namely B, component, Q, J component, and Q. i. Each of the components is extremely stable and has excellent physical properties, and their proportions determine the softening point, viscosity, and spinnability.

In the production of 100% membrane pitch, which is a raw material for long-fiber, high-strength, high-elastic carbon fibers, preliminary treatment involves heat treatment and aging of the H8 component extracted from the 85% distillate of petroleum-based hitch under reduced pressure. The preferable heating conditions for producing 100% mesophase pitch are heating temperature of 390°C to 410°C for 1 and 2 hours to 6 hours, and the preferable aging conditions are aging temperature of 310' to 330°C and 10 hours to gloss time. be.

Ru.

The non-oxidizing gas used in these heat treatments and aging treatments is the gas (
For example, hydrogen 6.0%, methane 74.6%, ethane 13.
3% propane, 3.6% propane, 1.3% butane, etc.) Propane and other naphtha fractions that do not become heavy can be mentioned.

The most distinctive feature of the present invention is that petroleum pitch made from desulfurized vacuum gas oil is distilled under reduced pressure to produce an 85-spot fraction.
First, the average molecular weight and composition of the precursor produced by pre-processing the H0 component extracted from this fraction are made uniform, and therefore the precursor is free from the effects of the crude oil type of petroleum-based pitch and the manufacturing method of petroleum-based pitch. It becomes possible to suppress it as much as possible. The composition of this precursor is a trace amount of ■, acid component B, component Q, and 8
．． The 100% mesophase pitch made from component Q and a small amount of component 16 has a low average molecular weight, and there is almost no H0 component in the low boiling point fraction, and B, component,
Q.S.

Ingredients and Q. i. It consists of several components, and the mixing ratio of these components is extremely effective in improving spinnability.

When this 100% mesophase pitch is melt-spun through several hundred to fine spinning holes, the amount of volatile components from the surface of the spinneret of the spinning hole is extremely small (because there is no H9 component) and the spinning properties are excellent. The speed is as fast as several hundred meters per minute, and it can be smoothly wound onto a bobbin for a long time with almost no yarn breakage, and the carbon fiber made by making this fiber infusible, calcination carbonization, and graphitization using conventional methods is extremely unique. As for its physical properties, it is possible to expect a long-fiber, high-strength, ultra-high-elasticity carbon fiber with a strand strength of 300 kg/III+12 or more and an elastic modulus of 70 T/rnys'' or more.

Example 1 Initial distillation 460 obtained by distilling petroleum pitch by-produced by thermal catalytic cracking (FCC) of desulfurized vacuum gas oil under reduced pressure to 85%
H00 min (average molecular weight 342, softening point 47°C to 49°C) produced by solvent extraction with hexane from the fraction with a final distillation temperature of
Blow propane gas into the temperature (°C) and raise the temperature to 400°C while stirring.
℃ for 6 hours to produce a pitch containing approximately 10% mesophase pitch, and this produced pitch is aged under a stream of non-oxidizing gas at a temperature of 320℃ for a period of time to fuse only the mesophase pitch in the produced pitch. The upper layer, which contains no mesophase pitch at all (H00 min. 14.88%, B. component 20
, 24 Chi, Q, S.

Ingredients 64.42%, Q. i, component sail 46%, this Q. i. Non-mesopitch (H, component less than 0.1%) is separated by the difference in specific gravity into mesophase pitch (the component is soluble when hydrogenated with lithium) and mesophase pitch in the lower layer, and the non-mesopitch in the upper layer is extracted by solvent extraction with hexane. , B, component 23.7
7%, Q. S. Ingredients 75.68%, Q. i. Ingredients 0.5
5 Ch) 100 parts of non-meso pitch that does not contain any menphase (B, component 12.03%, Q.S. component 87.37 yen, Q. 100 parts of component (i. 0.60 g) were mixed, and this mixture was heated at 400° C. for 2 hours while blowing gas and stirring to produce a pitch containing 45.5% mesophase pitch. This produced pitch is aged at a temperature of 320 °C under an air flow of Pro-Q gas, and only the mesophase pitch in the pitch is fused and becomes gigantic. B, component 12.03%, Q, S
, component 87, 37%, Q. i. component 0.60 chi) and the lower layer ioo chimesophase pitch (B, component 10.02
%, Q. S. Ingredient 49, 96%, Q. i. Ingredient 40.
02%) and is clearly separated and purified based on the difference in specific gravity.

The softening point of this 100% mesophase pitch for melt spinning is 272°C. In addition, non-meso pitch (B, component 12.03%, Q.S. component 87, 37%, Q.i. component 0. As for the 60-inch pitch, the upper layer of non-meso pitch which does not contain any mesophase pitch is applied thereto, which is separated when producing the 100-inch meso 7A pitch.

This 100% mesophase pitch was used for melt spinning, using a nozzle with 250 spinning holes and a spinning speed of 460 m.
Long-staple pitch-based fibers are wound onto a bobbin in 7 minutes without any yarn breakage, and then wound again, infusible with air at 340°C to create an infusible yarn, and then this infusible yarn is made into an infusible yarn. After carbonization in nitrogen gas, 2,700 in argon stream
It can be graphitized at ℃ to produce a high-strength, ultra-high modulus carbon fiber bundle with 250 long fibers.

This carbon fiber has a strand strength of 310 kg/mpr.
2. It is a long-fiber, high-strength, high-modulus carbon fiber that has a large elastic modulus of 72 T/ax" and extremely unique properties.

[Effects of the present invention]

The present invention pre-processes the H11 fraction extracted from petroleum-based pitch, thereby minimizing the influence of the oil type of the crude oil used as the raw material for petroleum-based pitch and the sealing method of the petroleum pitch, and producing homogenized H11 fraction. A non-mesopitch containing no mesophase pitch is produced by heat treatment, aging and fusing as a raw material, and difinate, which is produced by solvent extraction of this non-mesopitch with an aliphatic hydrocarbon having 6 to 8 carbon atoms, is melted as a precursor. Produces 100% mesophase pitch for spinning.

This 100% mesophase pitch has a minute amount of H11,
B, component, Q, S, component and Q. i. Made from ingredients,
These ratios are also reasonable, and the physical properties of mesophase pitch are extremely unique.

Claims (1)

[Claims] 1) H. Component: Component extracted from sample gr with 150 CC of heptane at a temperature of 98.4°C. B. Ingredients: H. H. obtained by solvent extraction of the components. A component extracted from insoluble matter using 150cc of benzene at a temperature of 80.1°C. Q. S. Ingredients: B. B obtained by solvent extraction of components
．． A component extracted from insoluble matter using 150cc of quinoline at a temperature of 237°C. Q. i. Ingredients: Q. S. Insoluble matter obtained by solvent extraction of components. When defined as, initial distillation 460°C to final distillation 56 by vacuum distillation of petroleum pitch produced by thermal catalytic cracking (FCC) of desulfurized vacuum gas oil.
0°C fraction (H. component 20% to 84%, B. component 16%
H. The ingredients are used as raw materials, and a non-oxidizing gas is blown into them at a temperature of 380°C to 420°C under reduced pressure or normal pressure.
℃ for 2 hours to 10 hours with stirring to produce a pitch containing 5% to 15% mesophase pitch, and the resulting pitch was heated under a stream of non-oxidizing gas at a temperature of 300 degrees Celsius to 350 degrees Celsius for 10 hours to 40 hours. By aging for a time, only the mesophase pitch in the pitch is fused and becomes gigantic, and at this aging temperature, the upper layer is non-meso pitch that does not contain any mesophase pitch (10.0% → 17.0%, B. component 20.0%)
→39.0%, Q. S. Ingredients 42.0% → 66.0%,
Q. i. The non-mesophase pitch in the upper layer is extracted with a solvent using an aliphatic hydrocarbon having 6 to 8 carbon atoms to form roughinate (H . component 0.5% or less, B. component 22.0% → 44.0%, Q.S. component 51.0% → 7
8.0%, Q. i. This roughinate was used as a precursor of pitch for melt spinning, and a non-oxidizing gas was blown into it under normal pressure or pressurization, and the temperature was 380°C to 420°C for 2 hours with stirring. The resulting pitch is heated for 6 hours to produce a pitch containing 20% to 60% mesophase pitch, and the resulting pitch is aged in a stream of non-oxidizing gas at a temperature of 300°C to 350°C for 10 to 40 hours to produce pitch. At this ripening temperature, only the mesophase pitch in the middle layer is fused and becomes gigantic.
．． Ingredients 10.0% → 35.0%, Q. S. Ingredient 61.0
% → 89.0%, Q. i. component 0.4% → 4.0%, confirmed by polarizing microscope) and the lower layer 100% mesophase pitch (H. component 0.05% or less, B. component 8.0% → 21.
0%, Q. S. Ingredients 42.0% → 58.0%, Q. i.
A method for producing 100% mesophase pitch for melt spinning, which is characterized in that it is clearly separated into two components (28.0% → 45.0%, easily confirmed with a polarizing microscope) based on the difference in specific gravity. 2) The precursor (H. component 0.5% or less, B. component 22.
0% → 44.0%, Q. S. Ingredients 51.0% → 78.0
%, Q. i. 0.8% or less) per 100 parts
Non-mesopitch that does not contain any mesophase pitch in the upper layer that is produced as a by-product when producing 0% mesophase pitch (H. component 0.1% or less, B. component 10.0% → 35.0%, Q
．． S. Ingredients 61.0% → 89.0%, Q. i. Ingredients 0.
4% → 4.0%) and heated at a temperature of 380°C to 420°C for 2 to 6 hours with stirring and blowing non-oxidizing gas under normal or pressurized conditions to form mesophase pitch. Pitch containing 20% to 60% of
Aging is performed at 350°C for 10 to 40 hours to fuse only the mesophase pitch in the pitch to a large size. B. Ingredients 10.0%
→35.0%, Q. S. Ingredients 61.0% → 89.0%,
Q. i. component 0.4% → 4.0%) and the lower layer 100% mesophase pitch (H. component 0.05% or less, B. component 8.0% → 21.0%, Q.S. component 42.0% →58
．． 0%, Q. i. 2. The method according to claim 1, characterized in that the component is clearly separated into components (28.0% → 45.0%) based on the difference in specific gravity. 3) Non-meso pitch that does not contain any mesophase pitch in the upper layer that is produced as a by-product when producing 100% mesophase pitch (H. component 0.1% or less, B. component 10.0% → 35
．． 0%, Q. S. Ingredients 61.0% → 89.0%, Q. i
．． 0.4% → 4.0%) was heated to 38°C while blowing in non-oxidizing gas and stirring under normal or pressurized conditions.
Heating at 0°C to 420°C for 1 to 4 hours to produce pitch containing 20% to 60% mesophase pitch,
Only the mesophase pitch in this generated pitch is fused and becomes large, and at the ripening temperature, the upper layer is a non-mesopitch that does not contain any mesophase pitch (H. component 0.1% or less, B.
Ingredients 10.0% → 35.0%, Q. S. Ingredients 61.0%
→89.0%, Q. i. component 0.4% to 4.0%) and the lower layer 100% mesophase pitch (H. component 0.05
% or less, B. Ingredients 8.0% → 21.0%, Q. S. Ingredients 42.0% → 58.0%, Q. i. Ingredients 28.0% → 4
5.0%) and 5.0%).