CN104610994A - Preparation method of mesophase pitch with low softening point and high mesophase content - Google Patents
Preparation method of mesophase pitch with low softening point and high mesophase content Download PDFInfo
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- CN104610994A CN104610994A CN201510023348.7A CN201510023348A CN104610994A CN 104610994 A CN104610994 A CN 104610994A CN 201510023348 A CN201510023348 A CN 201510023348A CN 104610994 A CN104610994 A CN 104610994A
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- pitch
- carbonization
- cycloalkyl
- mesophase pitch
- mesophase
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10C—WORKING-UP PITCH, ASPHALT, BITUMEN, TAR; PYROLIGNEOUS ACID
- C10C3/00—Working-up pitch, asphalt, bitumen
- C10C3/02—Working-up pitch, asphalt, bitumen by chemical means reaction
- C10C3/026—Working-up pitch, asphalt, bitumen by chemical means reaction with organic compounds
Abstract
The invention provides a preparation method of mesophase pitch with a low softening point and high mesophase content. The method comprises steps as follows: (1),in the inert atmosphere or the nitrogen atmosphere, naphthenic base atmospheric pressure residual oil distillate at the temperature of 480-560 DEG C and catalytic cracking oil slurry of naphthenic base reduced pressure distillate oil are subjected to primary co-carbonization treatment, and primary co-carbonized pitch is obtained; (2), in the inert atmosphere or the nitrogen atmosphere, the primary co-carbonized pitch and the catalytic cracking oil slurry of the naphthenic base reduced pressure distillate oil are subjected to secondary co-carbonization treatment, and the mesophase pitch is obtained. The defect of raw materials can be effectively remedied with two-time co-carbonization methods, so that the purity of mesophase pitch is improved, the optical structure of the prepared mesophase pitch is in a wide-area streamline body form, the softening point is lower and is about 200-260 DEG C, the spinnability is good, and the mesophase pitch is excellent precursor for preparation of a high-performance carbon fiber high-grade carbon material.
Description
Technical field
The invention belongs to senior new carbon high-quality precursor power technical field, be specifically related to a kind of method preparing the mesophase pitch of phase content between low softening point senior middle school with the catalytically cracked oil of cycloalkyl long residuum 480 ~ 560 DEG C of cuts and cycloalkyl vacuum distillate for raw material.
Background technology
From early 1980s, senior new carbon is fast-developing, is widely used in the various fields such as national defense industry, aerospace, hard-core technology, daily life, has the special status do not replaced in whole materialogy.The various excellent properties of mesophase pitch become the high-quality presoma preparing senior carbon material, are more and more paid attention to.
Mesophase pitch, to be a kind of by relative molecular mass be 370 ~ 2000 multiple flat plate-like or the mixture that forms of bar-shaped condensed-nuclei aromatics, be again mesomorphic phase pitch, have optics anisotropic, its raw material can be that plain asphalt, mink cell focus, coal tar, aromatic compound are as naphthalene and composition thereof etc.For preparing high-new Carbon Materials, general requirement mesophase pitch softening temperature and ash content low, heteroatoms is few, and have good solubility and mobility, molecular arrangement is regular, presents that wide area is streamlined to be melted greatly and body.And the quality of mesophase pitch is strongly depend on initial feed and concrete preparation condition.
Generally, raw material aromaticity content is high, weight ratio about 50 ~ 90%, fragrance number of rings is less, R=2 ~ 4 ring, and the side chain of aromatic ring is short and lack, ash content <0.05wt%, vanadium and nickel element content≤50 μ g/g, quinoline insolubles <1wt%, be suitable for preparing high-quality mesophase pitch.At present, the method preparing mesophase pitch mainly contains direct thermal polycondensation process, catalyzed polycondensation method, hydrogenation-alkylation modification method and Co carbonization method etc., but these methods all also exist deficiency.Direct thermal polycondensation process is higher to ingredient requirement, and the Structure and Properties of most of raw material is also not suitable for directly carrying out thermal response, and temperature of reaction is general higher, and the softening temperature of obtained mesophase pitch is higher, and molecular weight distribution is wider, and economic worth is lower.Catalyzed polycondensation method obtains howling success in asphalt-based carbon fiber industrialization, and Japanese Patent Laid-Open 1-139621, Unexamined Patent 1-254796 utilize HF/BF
3catalyzed polycondensation method has just obtained the mesophase pitch of phase content between low softening point senior middle school, but the Lewis acid of this kind of method use and solid super acid catalyst meeting etching apparatus, investment is large, operational hazards, and is difficult to remove.Hydrogenation-alkylation modification method is mainly through adding the realizations such as hydrogen supply agent, and technics comparing is complicated, high to equipment requirements, course of industrialization difficulty.Co carbonization method utilizes additive to make up single raw material mix and composition defect, improve its charing performance, but reaction stability is wayward.
The ubiquitous problem of mesophase pitch preparation method of current existence is mesophase pitch product, softening temperature higher (>300 DEG C), complicated process of preparation, and some catalyzer, additive are residual can affect subsequent product performance.
Summary of the invention
It is complicated that the present invention mainly solves existing mesophase pitch method of preparing, the high and problem that mesophase pitch softening temperature is higher, content is lower generated of cost.
In order to solve the problems of the technologies described above, the invention provides a kind of method preparing mesophase pitch.
The method preparing mesophase pitch provided by the present invention, comprises the steps:
(1) under inert atmosphere or nitrogen atmosphere, the catalytically cracked oil of cycloalkyl long residuum 480 ~ 560 DEG C of cuts and cycloalkyl vacuum distillate is carried out a Co carbonization process, obtains a Co carbonization pitch;
(2) under inert atmosphere or nitrogen atmosphere, the catalytically cracked oil of a described Co carbonization pitch and cycloalkyl vacuum distillate is carried out the process of secondary Co carbonization, obtains mesophase pitch.
In aforesaid method step (1), the cycloalkane structure content in described cycloalkyl long residuum 480 ~ 560 DEG C of cuts on aromatic nucleus is 5wt%-35wt%, and the alkyl group side chain content on aromatic nucleus is 10wt%-50wt%.
The fragrant number of rings of the catalytically cracked oil of described cycloalkyl vacuum distillate is 2-4, and aromaticity content is 50-90wt%.
The mass ratio of the catalytically cracked oil of described cycloalkyl long residuum 480 ~ 560 DEG C of cuts and described cycloalkyl vacuum distillate is 10:1-5, specifically can be 10:1,10:2,10:3 or 10:4.
A described Co carbonization is treated to: under inert atmosphere or nitrogen atmosphere, after the catalytically cracked oil of described cycloalkyl long residuum 480-560 DEG C of cut and described cycloalkyl vacuum distillate is warming up to 450-500 DEG C (as 470 DEG C, 480 DEG C, 490 DEG C or 500 DEG C) thermal treatment 0.5-1 hour (as 0.5h, 40min or 50min) in confined conditions, pressure release is to normal pressure, holding temperature, 450-500 DEG C of thermal treatment 0.5-1 hour (as 0.5 hour or 0.6 hour), obtains a Co carbonization pitch.
The softening temperature of the Co carbonization pitch prepared is 80-100 DEG C, and ash content < 0.01wt%, H/C (atomic ratio) are 1.36-1.46.
In aforesaid method step (2), the mass ratio of the catalytically cracked oil of a described Co carbonization pitch and described cycloalkyl vacuum distillate is 10:1-3, specifically can be 10:1,10:2 or 10:3.
In aforesaid method step (2), the pressure of described secondary Co carbonization process is 0.1-4MPa, specifically can be 1MPa, 2MPa, 3MPa or 4MPa.
The temperature of described secondary Co carbonization process is 380-430 DEG C, specifically can be 380 DEG C, 390 DEG C, 420 DEG C or 430 DEG C.
The time of described secondary Co carbonization process is 8-15 hour, specifically can be 8 hours, 10 hours or 12 hours.
The mesophase pitch optical texture prepared is large wide area fairing, and softening temperature is 200-260 DEG C, H/C (atomic ratio) is 0.35-0.6, and mesophase spherule content is 85vol%-100vol%.
The mesophase pitch prepared by aforesaid method also belongs to protection scope of the present invention.
The present invention takes secondary Co carbonization method.The catalytically cracked oil fragrance number of rings 2 ~ 4 of cycloalkyl vacuum distillate, aromaticity content 50-90wt%, relative molecular weight distribution is narrow, containing more cycloalkane structure, contributes to hydrogen transfer reactions occurs, is conducive to the carrying out of condensation polymerization reaction; And alkyl group side chain in cycloalkyl long residuum 480 ~ 560 DEG C of cuts on aromatic nucleus is relatively many, be easy to cracking reaction occurs, polycondensation activity is higher, easily excessive polycondensation occurs.Therefore, in the reaction of first time Co carbonization process employing high temperature, short time, effectively can make the long side chain fracture of the alkyl in cycloalkyl long residuum 480 ~ 560 DEG C of cuts, avoid the disadvantageous effect to secondary carbonization process.
A carbonizing production is carried out secondary Co carbonization with the catalytically cracked oil of cycloalkyl vacuum distillate with 10:1-3 mass ratio again, in a carbonizing production, long alkyl group side chain content greatly reduces, and the catalytically cracked oil of cycloalkyl vacuum distillate add by hydrogen transfer reactions, reduce the softening temperature of product, be conducive to the generation of mesophase pitch.
The present invention's beneficial effect compared with existing preparation method is:
(1) raw material that the present invention relates to is cheap and easy to get, corrosion-free to equipment;
(2) the present invention is simple to operation, industrialization promotion and the application being beneficial to preparation scheme with short production cycle;
(3) the common charcoal method of employing secondary effectively can make up the defect between raw material, improve the purity of mesophase pitch, and the optical texture of the mesophase pitch prepared is large wide area fairing, softening temperature lower (200-260 DEG C), good spinnability are the excellent presomas preparing the senior carbon materials such as high-performance carbon fibre.
Embodiment
Below by specific embodiment, the present invention will be described, but the present invention is not limited thereto.
The experimental technique used in following embodiment if no special instructions, is ordinary method; Reagent used in following embodiment, material etc., if no special instructions, all can obtain from commercial channels.
The fragrant number of rings of the catalytically cracked oil of the SZ36-1 cycloalkyl vacuum distillate adopted in following embodiment is 2-4 ring, and aromaticity content is 71-75wt%.
Cycloalkane structure content in SZ36-1 cycloalkyl long residuum 480 ~ 560 DEG C of cuts adopted in following embodiment on aromatic nucleus is 28-35wt%, and the alkyl group side chain content on aromatic nucleus is 31-35wt%.
In following embodiment, the optical texture of mesophase pitch and content are obtained by polarized light microscope observing; Softening temperature adopts conventional needling method to test; H/C adopts elemental analyser to measure.
Embodiment 1
Being mixed with SZ36-1 cycloalkyl long residuum 480 ~ 560 DEG C of cut 200g by SZ36-1 cycloalkyl vacuum distillate catalytically cracked oil 20g adds in stainless steel autoclave, pass into airtight described autoclave after nitrogen purging displaced air 3 times, at the uniform velocity be warming up to 100 DEG C with 3 DEG C/min, start and stir; Continue at the uniform velocity to be warming up to 480 DEG C of thermal treatment 0.5h, pressure release is to normal pressure, holding temperature was 480 DEG C of constant thermal treatments 0.5 hour, (softening temperature of a described Co carbonization pitch is 83 DEG C to obtain a Co carbonization pitch, ash content is < 0.01wt%, H/C (atomic ratio) is 1.44); Get a described Co carbonization pitch 100g to mix with SZ36-1 cycloalkyl vacuum distillate catalytically cracked oil 10g, 1MPa is forced under nitrogen atmosphere, at the uniform velocity stir, 380 DEG C of thermal treatment 12h, relief pressure, slow cooling, obtain 100vol% optics anisotropic, the streamlined mesophase pitch of wide area, softening temperature 230 DEG C, H/C is 0.59, and yield is 35.7wt%.
Embodiment 2
Being mixed with SZ36-1 cycloalkyl long residuum 480 ~ 560 DEG C of cut 200g by SZ36-1 cycloalkyl vacuum distillate catalytically cracked oil 40g adds in stainless steel autoclave, after passing into nitrogen purging displaced air 3 times, airtight described autoclave is at the uniform velocity warming up to 100 DEG C with 3 DEG C/min, starts and stirs; Continue to be warming up to 490 DEG C of thermal treatment 50min, pressure release is to normal pressure, holding temperature was 490 DEG C of constant thermal treatments 0.6 hour, (softening temperature of a described Co carbonization pitch is 87 DEG C to obtain a Co carbonization pitch, ash content is < 0.01wt%, H/C (atomic ratio) is 1.41); A described Co carbonization pitch 100g is mixed with SZ36-1 cycloalkyl vacuum distillate catalytically cracked oil 20g, 2MPa is forced under nitrogen atmosphere, at the uniform velocity stir, 430 DEG C of thermal treatment 8h, relief pressure, slow cooling, obtain 100vol% optics anisotropic, the streamlined mesophase pitch of wide area, softening temperature 245 DEG C, H/C is 0.55, and yield is 34.5wt%.
Embodiment 3
Being mixed with SZ36-1 cycloalkyl long residuum 480 ~ 560 DEG C of cut 200g by SZ36-1 cycloalkyl vacuum distillate catalytically cracked oil 60g adds in stainless steel autoclave, after passing into nitrogen purging displaced air 3 times, airtight described autoclave is at the uniform velocity warming up to 120 DEG C with 3 DEG C/min, starts and stirs; At temperature of reaction 470 DEG C of thermal treatment 40min, pressure release is to normal pressure, holding temperature was 470 DEG C of constant thermal treatments 0.5 hour, (softening temperature of a described Co carbonization pitch is 93 DEG C to obtain a Co carbonization pitch, ash content is < 0.01wt%, H/C (atomic ratio) is 1.39); A described Co carbonization pitch 100g is mixed with SZ36-1 cycloalkyl vacuum distillate catalytically cracked oil 30g, 3MPa is forced under nitrogen atmosphere, at the uniform velocity stir, 420 DEG C of thermal treatment 8h, relief pressure, slow cooling, obtain 100vol% optics anisotropic, the streamlined mesophase pitch of wide area, softening temperature 240 DEG C, H/C is 0.53, and yield is 32.9wt%.
Embodiment 4
Being mixed with SZ36-1 cycloalkyl long residuum 480 ~ 560 DEG C of cut 200g by SZ36-1 cycloalkyl vacuum distillate catalytically cracked oil 80g adds in stainless steel autoclave, after passing into nitrogen purging displaced air 3 times, airtight described autoclave is at the uniform velocity warming up to 130 DEG C with 3 DEG C/min, starts and stirs; Continue at the uniform velocity to be warming up to 500 DEG C of thermal treatment 0.5hr, pressure release is to normal pressure, holding temperature was 500 DEG C of constant thermal treatments 0.6 hour, (softening temperature of a described Co carbonization pitch is 97 DEG C to obtain a Co carbonization pitch, ash content is < 0.01wt%, H/C (atomic ratio) is 1.37); Get a described Co carbonization pitch 100g to mix with SZ36-1 cycloalkyl vacuum distillate catalytically cracked oil 20g, 4MPa is forced under nitrogen atmosphere, at the uniform velocity stir, 390 DEG C of thermal treatment 10h, relief pressure, slow cooling, obtain 100vol% optics anisotropic, the streamlined mesophase pitch of wide area, softening temperature 250 DEG C, H/C is 0.49, and yield is 30.6wt%.
Claims (9)
1. prepare a method for mesophase pitch, comprise the steps:
(1) under inert atmosphere or nitrogen atmosphere, the catalytically cracked oil of cycloalkyl long residuum 480 ~ 560 DEG C of cuts and cycloalkyl vacuum distillate is carried out a Co carbonization process, obtains a Co carbonization pitch;
(2) under inert atmosphere or nitrogen atmosphere, the catalytically cracked oil of a described Co carbonization pitch and cycloalkyl vacuum distillate is carried out the process of secondary Co carbonization, obtains mesophase pitch.
2. method according to claim 1, it is characterized in that: in described method steps (1), the mass content of the cycloalkane structure in described cycloalkyl long residuum 480 ~ 560 DEG C of cuts on aromatic nucleus is 5%-35%, and the mass content of the alkyl group side chain on aromatic nucleus is 10%-50%;
The fragrant number of rings of the catalytically cracked oil of described cycloalkyl vacuum distillate is 2-4, and the mass content of aromatic hydrocarbons is 50%-90%.
3. method according to claim 1 and 2, is characterized in that: in described method steps (1), and the mass ratio of the catalytically cracked oil of described cycloalkyl long residuum 480 ~ 560 DEG C of cuts and described cycloalkyl vacuum distillate is 10:1-5.
4. the method according to any one of claim 1-3, it is characterized in that: in described method steps (1), a described Co carbonization is treated to: under inert atmosphere or nitrogen atmosphere, after the catalytically cracked oil of described cycloalkyl long residuum 480-560 DEG C of cut and described cycloalkyl vacuum distillate is warming up to 450-500 DEG C of thermal treatment 0.5-1 hour in confined conditions, pressure release is to normal pressure, holding temperature, at 450-500 DEG C of thermal treatment 0.5-1 hour, obtains a Co carbonization pitch;
The softening temperature of the described Co carbonization pitch prepared is 80-100 DEG C, and ash content < 0.01%, H/C is 1.36-1.46.
5. the method according to any one of claim 1-4, is characterized in that: in described method steps (2), and the mass ratio of the catalytically cracked oil of a described Co carbonization pitch and described cycloalkyl vacuum distillate is 10:1-3.
6. the method according to any one of claim 1-5, is characterized in that:
In described method steps (2), the pressure of described secondary Co carbonization process is 0.1MPa-4MPa;
In described method steps (2), the temperature of described secondary Co carbonization process is 380 DEG C-430 DEG C;
In described method steps (2), the time of described secondary Co carbonization process is 8 hours-15 hours.
7. the method according to any one of claim 1-6, is characterized in that: described in the mesophase pitch for preparing be large wide area fairing, softening temperature is 200 DEG C-260 DEG C, and the volume content of mesophase spherule is 85%-100%.
8. the mesophase pitch that the method according to any one of claim 1-7 prepares.
9. mesophase pitch according to claim 8, is characterized in that: described mesophase pitch is large wide area fairing, and softening temperature is 200 DEG C-260 DEG C, and the volume content of mesophase spherule is 85%-100%, H/C is 0.35-0.6.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106435840A (en) * | 2016-10-21 | 2017-02-22 | 中国石油大学(华东) | Preparation method of asphalt based carbon fiber |
| CN106544758A (en) * | 2016-10-21 | 2017-03-29 | 中国石油大学(华东) | A kind of preparation method of high modulus pitch-based carbon fiber |
| CN108485694A (en) * | 2018-04-11 | 2018-09-04 | 北京化工大学 | A method of carbonizatin method prepares high-quality mesophase pitch altogether |
| CN109610049A (en) * | 2018-12-18 | 2019-04-12 | 武汉科技大学 | A kind of method of the poly- response regulatory mesophase pitch the Nomenclature Composition and Structure of Complexes of heat together |
| WO2021232561A1 (en) * | 2020-05-22 | 2021-11-25 | 中国石油大学(华东) | Preparation methods for mesophase pitch and high modulus pitch-based carbon fiber |
-
2015
- 2015-01-16 CN CN201510023348.7A patent/CN104610994A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106435840A (en) * | 2016-10-21 | 2017-02-22 | 中国石油大学(华东) | Preparation method of asphalt based carbon fiber |
| CN106544758A (en) * | 2016-10-21 | 2017-03-29 | 中国石油大学(华东) | A kind of preparation method of high modulus pitch-based carbon fiber |
| CN106435840B (en) * | 2016-10-21 | 2018-09-11 | 中国石油大学(华东) | A kind of preparation method of asphalt base carbon fiber |
| CN108485694A (en) * | 2018-04-11 | 2018-09-04 | 北京化工大学 | A method of carbonizatin method prepares high-quality mesophase pitch altogether |
| CN109610049A (en) * | 2018-12-18 | 2019-04-12 | 武汉科技大学 | A kind of method of the poly- response regulatory mesophase pitch the Nomenclature Composition and Structure of Complexes of heat together |
| CN109610049B (en) * | 2018-12-18 | 2021-09-14 | 武汉科技大学 | Method for regulating and controlling composition and structure of mesophase pitch through co-thermal polymerization |
| WO2021232561A1 (en) * | 2020-05-22 | 2021-11-25 | 中国石油大学(华东) | Preparation methods for mesophase pitch and high modulus pitch-based carbon fiber |
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