EP0044714A2
Expired / Lapsed
EP
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Process for producing mesophase pitch
Assignee: Tonen General Sekiyu KK
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Filing: 1981-07-16
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Granted: —
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Expires: 2001-07-16
Abstract
Abstract A substantially uniform mesophase pitch is prepared by treating a mesophase forming pitch material at elevated temperatures above about 380°C to produce a mixture of mesophase and non-mesophase pitch containing about 20% to about 80% mesophase. The mixture is then maintained at a temperature below about 400°C for a time sufficient to allow the mesophase to coalesce and settle as a lower separable layer. A mesophase pitch so produced may contain from 90 to 100% mesophase with a softening point of less than 320°C.
Inventors
- 👤 Igarashi Seiko
- 👤 Izumi Takayuki
- 👤 Naito Tsutomu
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 18:23
CPC Classifications
C; C10; C10C; C10C3/00; C10C3/002; D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/145
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
99 words
l. A process for producing a mesophase pitch characterised by: (1) heat-treating a pitch forming material at elevated temperatures above about 380° C whereby thermal cracking and polycondensing reactions occur providing a mixture of mesophase and non- mesophase pitch containing about 20-80% of mesophase, (2) allowing the mesophase to settle at a temperature of below about 400°C to accumulate the mesophase portion of a higher density as a lower layer while it is allowed to grow and to age, and (3) separating the lower mesophase layer from an upper layer principally comprising nonmesophase pitch portion of a lower density.
Claim 2
Dependent Claim
30 words
A process for producing a mesophase pitch according to Claim 1 wherein the pitch forming material comprises hydrocarbons of a boiling point of at least about 400°C as main components.
Claim 3
Dependent Claim
39 words
A process for producing a mesophase pitch according to Claim 1 or 2 wherein the pitch forming material is heat-treated at a temperature in the range of about 380°C to about 460°C whereby thermal cracking and polycondensation reactions occur.
Claim 4
Dependent Claim
39 words
A process for producing a mesophase pitch according to Claim 1 or 2 wherein the pitch forming material is heat-treated at a temperature in the range of about 400°C to about 440°C whereby thermal cracking and polycondensing reactions occur.
Claim 5
Dependent Claim
58 words
A process for producing a mesophase pitch according to any preceding claim wherein the mesophase portion of the mixture is allowed to settle at a temperature in the range of from about 350°C to about 400°C to accumulate the mesophase portion of a higher density as a lower layer while it is allowed to gr and to age.
Claim 6
Dependent Claim
41 words
A process for producing a mesophase pitch according to any of claims 1 to 4 wherein the mixture is kept at a temperature in the range of from about 360°C to about 390°C to effect the aging and settling of mesophase.
Claim 7
Dependent Claim
36 words
The process for producing a mesophase pitch according to any preceding claim wherein the mesophase of the lower layer is from 90 to 100% mesophase having a softening point of less than about 3200 C .
Claim 8
Dependent Claim
35 words
A process for producing a mesophase pitch according to Claim 1 wherein the pitch forming material is heat-treated for a time sufficient to produce from about 40% to about 70% mesophase based on the mixture.
Claim 9
Dependent Claim
33 words
A process for producing a mesophase pitch according to any preceding claim wherein the upper layer principally comprising non-mesophase pitch portion is recycled to the heat-treating step whereby thermal and cracking/polycondensation reactions occur.
References Cited (Backward Citations)
No citation records indexed.
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