EP0146170A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Process for purifying 2,6 - xylenol
Assignee: Enichem SpA
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Filing: 1984-11-26
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Granted: —
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Expires: 2004-11-26
Abstract
Abstract Process for purifying raw 2,6-xylenol, comprising the following stages, carried out in succession:- melting of raw 2,6-xylenol;- slow and uniform cooling of said molten raw 2,6-xylenol until at least from 60% to 100% of its mass is separated as crystal solid;-gradual heating of said crystal solid, after having separated the possibly remaining liquid fraction, up to a highest temperature value lower by 0,1-5 °C, then the solidification temperature of 2,6-xylenol, in order to causing surface melting on said crystals;- separation of the thus obtained molten liquid phase and recovery of purified 2,6-xylenol.
Inventors
- 👤 Jerzy Bialek
- 👤 Marek Plesnar
- 👤 Janina Werle
- 👤 Jan Bialy
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 08:46
CPC Classifications
C; C07; C07C; C07C37/00; C07C37/68; C07C37/70; C07C37/84
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
120 words
Process for the purification of raw 2,6-xylenol, characterized in that: a) raw 2,6-xylenol is molten; b) said molten raw 2,6-xylenol is cooled, in a slow and uniform way, at a rate of from 0,1 to 10°C/hour, until al least 60% to 100% of the mass is separated as a crystalline solid; c) said crystalline solid is gradually heated, after having separated the liquid molten fraction possibly remaining, in a time of from 1 to 12 hours, up to a maximum temperature value lower by 0,1 - 5°C than the solidification temperature of 2,6-xylenol, so as to cause the melting on the surface of said crystals; d) the molten liquid fraction so obtained is separated and purified solid 2,6-xylenol is recovered.
Claim 2
Dependent Claim
120 words
Process for the purification of raw 2,6-xylenol, characterized in that: a) raw 2,6-xylenol is molten; b) said molten raw 2,6-xylenol is cooled, in a slow and uniform way, at a rate of from 0,1 to 10°C/hour, until al least 60% to 100% of the mass is separated as a crystalline solid; c) said crystalline solid is gradually heated, after having separated the liquid molten fraction possibly remaining, in a time of from 1 to 12 hours, up to a maximum temperature value lower by 0,1 - 5°C than the solidification temperature of 2,6-xylenol, so as to cause the melting on the surface of said crystals; d) the molten liquid fraction so obtained is separated and purified solid 2,6-xylenol is recovered.
Claim 3
Dependent Claim
30 words
Process as claimed in claim 1, characterized in that the raw 2,6-xylenol which is submitted to the purification has a content of 2,6-xylenol of from about 95% to about 98%.
Claim 4
Dependent Claim
27 words
Process as claimed in claim 1, characterized in that in the step b the cooling is carried out at a cooling rate of from 1 to 2°C/hour.
Claim 5
Dependent Claim
26 words
Process as claimed in claim 1, characterized in that in the step b the cooling is carried out till to solidify about 80% of charged batch.
Claim 6
Dependent Claim
22 words
Process as claimed in claim 1,' characterized in -that the molten liquid fraction which is formed in step c is collected continuously.
Claim 7
Dependent Claim
22 words
Process as claimed in claim 1, characterized in that the liquid molten fraction which is formed in step c is collected intermittently.
Claim 8
Dependent Claim
29 words
Process as claimed in claim 1, characterized in that it is carried out in a tube nest crystallizer, equipped with a heat exchange fluid externally to the same tubes.
References Cited (Backward Citations)
GB1066032A
Cited
FR1583244A
Cited
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