CN1024098C - Process of para-tertiary butyl catechol recovery - Google Patents
Process of para-tertiary butyl catechol recovery Download PDFInfo
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- CN1024098C CN1024098C CN 88103370 CN88103370A CN1024098C CN 1024098 C CN1024098 C CN 1024098C CN 88103370 CN88103370 CN 88103370 CN 88103370 A CN88103370 A CN 88103370A CN 1024098 C CN1024098 C CN 1024098C
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- butyl catechol
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Abstract
The present invention relates to a method of recovering high-purity para-tert-butyl catechol from para-tert-butyl catechol residual liquid. Through rectifying the para-tert-butyl catechol residual liquid under normal decompression or recrystallizing the para-tert-butyl catechol collected after rectification in an aliphatic hydrocarbon solvent, powdery crystals of para-tert-butyl catechol in the purity of 95.0 to 99.9% and the melting point above 52 DEG C can be obtained. The para-tert-butyl catechol recovered with the invented method can be used as a polymerization retarder for polymeric monomers.
Description
The present invention relates to a kind of from gathering the method for the high purity of usefulness to t-butyl catechol to reclaiming resistance the t-butyl catechol raffinate, it comprises the rectifying to the t-butyl catechol raffinate, or more collected is being carried out recrystallization to t-butyl catechol in aliphatic solvents after the rectifying.
To t-butyl catechol is a kind of high-efficiency polymerization inhibitor.In production, storage or the course of conveying of polymerization single polymerization monomers such as divinyl, vinylbenzene, isoprene, chloroprene, often need add t-butyl catechol, cause obstruction to equipment or pipeline to prevent these monomer autohemagglutinations.
But, before polymerization single polymerization monomer carries out polymerization, often need again to remove in polymerization single polymerization monomer, rise inhibition to t-butyl catechol, to guarantee normally carrying out of polymerization process.Like this, will produce the t-butyl catechol raffinate.
Past all is directly all discharging or most of discharging to the t-butyl catechol raffinate, this not only wasted price higher to t-butyl catechol, but also can pollute.
Synthetic Rubber Plant of Beijing Yanshan Petro-Chemical Industry Corp. had once delivered relevant a kind of method that t-butyl catechol is reclaimed on " Yanshan Mountain oiling " first phase in 1980.This method is by the t-butyl catechol raffinate is carried out simple distillation removing to reclaim after light constituent and the heavy constituent and obtain t-butyl catechol what discharge in the butadiene extraction unit, and reclaimed t-butyl catechol is returned in the extraction plant used.But what this method reclaimed is dark-brown to t-butyl catechol; When especially foreign matter content was higher in to the t-butyl catechol raffinate, the foreign matter content to t-butyl catechol that this method reclaimed was also higher.These impurity are accumulation gradually in the process of t-butyl catechol constantly being returned use, make the foreign matter content in the t-butyl catechol of recovery more and more higher, thereby the reduction more and more significantly of its polymerization inhibition effect, so that can't again the stopper as polymerization single polymerization monomer in its return mechanism be used.
The object of the present invention is to provide a kind of to reclaiming highly purified method the t-butyl catechol raffinate to t-butyl catechol.
Another object of the present invention is can be used as the stopper of polymerization single polymerization monomers such as divinyl, vinylbenzene, isoprene, chloroprene by method provided by the invention is resulting to t-butyl catechol, thereby has improved the utilization ratio to t-butyl catechol.
Purpose of the present invention can reach by following measure: polymerization single polymerization monomer removes and to what produce behind the t-butyl catechol the t-butyl catechol raffinate is carried out normal rectification under vacuum in rectifying tower, or with collected in the rectifying t-butyl catechol is carried out recrystallization in aliphatic solvents again after rectifying.
Saidly contain debris, wherein can contain water, also can not contain water t-butyl catechol to what the t-butyl catechol raffinate was meant that polymerization single polymerization monomer produced when removing t-butyl catechol.
Said polymerization single polymerization monomer can be divinyl, vinylbenzene, isoprene or chloroprene etc.
Said rectifying tower can be a packing tower, also can be the rectifying tower of sieve-tray tower or other types, and the material of rectifying tower can be carbon steel or other available materials.
Said rectifying can be intermittently, also can be successive.Rectifying can be first atmospheric distillation and then rectification under vacuum, also can be rectification under vacuum from start to finish.Whole rectifying process needs to carry out under secluding air.
Said aliphatic solvents be meant aromaticity content be 0～10%(by weight), cycloalphatic hydrocarbon content be 0～50%(by weight) aliphatic hydrocarbon.Said aliphatic hydrocarbon can be the aliphatic hydrocarbon that contains 5 to 12 carbon atoms, as hexane or heptane etc.; Said aliphatic hydrocarbon also can be the fat hydrocarbon mixture that contains 5 to 12 carbon atoms, as contains the mixed alkanes of 5 to 9 carbon atoms, and perhaps boiling range is 40～120 ℃ a petroleum hydrocarbon, and preferably boiling range is 60～90 ℃ a petroleum hydrocarbon.
Rectifying is that absolute pressure is that environmental stress (is generally 1.013 * 10 in tower still temperature is 80～260 ℃, tower
5Pa)～0Pa(promptly carries out under 760～0mmHg).
Rectifying can be to carry out atmospheric distillation earlier to carry out rectification under vacuum then.In the atmospheric distillation process, tower still temperature is 80～200 ℃, and absolute pressure is that environmental stress (is generally 1.013 * 10 in the tower
5Pa, i.e. 760mmHg), can remove the light constituent impurity of boiling point below 150 ℃.Behind the light constituent impurity removal, carry out rectification under vacuum.In the rectification under vacuum process, tower still temperature is 80～260 ℃, and preferred temperature is 80～240 ℃, and preferably temperature is 80～220 ℃; Absolute pressure is 1.333 * 10 in the tower
4～0Pa(is 100～0mmHg), and preferable pressure is 7.998 * 10
3～0Pa(i.e. 60～0mmHg) optimum pressures is 5.332 * 10
3～0Pa(is 40～0mmHg).In the rectification under vacuum process, the tower internal pressure can be a certain pressure selected in the above-mentioned pressure range, also can gradually change in above-mentioned pressure range on demand.The rectification under vacuum process can remove the impurity below the t-butyl catechol boiling point, is collecting the t-butyl catechol cut under accordingly to the t-butyl catechol boiling point with selected pressure then.In whole rectifying process, control of reflux ratio is 1～20.As everyone knows, in rectifying, the recovered temperature of component is relevant with the tower internal pressure, when carrying out rectification under vacuum in the tower internal pressure scope that the present invention selectes, can collect the t-butyl catechol cut down at 160～210 ℃.The heavy component of t-butyl catechol is discharged at the bottom of tower, the cooling back is the solid matter of pitch shape.
Rectifying also can be all to carry out rectification under vacuum from start to finish.In the rectification under vacuum process, tower still temperature is 80～260 ℃, and preferred temperature is 80～240 ℃, and preferably temperature is 80～220 ℃; Absolute pressure is 1.333 * 10 in the tower
4～0Pa(is 100～0mmHg), and preferable pressure is 7.998 * 10
3～0Pa(i.e. 60～0mmHg) optimum pressures is 5.332 * 10
3～0Pa(is 40～0mmHg).In the rectification under vacuum process, the tower internal pressure can be a certain pressure selected in the above-mentioned pressure range, also can gradually change in above-mentioned pressure range on demand.The rectification under vacuum process can remove the impurity below the t-butyl catechol boiling point, is tackling the t-butyl catechol cut mutually with selected pressure then.In whole rectifying process, control of reflux ratio is 1～20.As everyone knows, in rectifying, the recovered temperature of component is relevant with the tower internal pressure, when carrying out rectification under vacuum in the tower internal pressure scope that the present invention selectes, can collect the t-butyl catechol cut down at 160～210 ℃.The heavy component of t-butyl catechol is discharged at the bottom of tower, the cooling back is the solid matter of pitch shape.
Rectifying can carry out in same tower, also can carry out in two or more towers respectively.
In rectifying, the add-on of the auxiliary agent of prevention oxidations such as sodium bisulfite is that 0～2%(is by the weight to the t-butyl catechol raffinate that drops into).That is to say, in rectifying, can not add sodium bisulfite (add-on that is sodium bisulfite is 0), also can add the sodium bisulfite (by the weight that drops into) below 2% or 2% the t-butyl catechol raffinate.
By the resulting purity to t-butyl catechol of rectifying with relevant to the foreign matter content in the t-butyl catechol raffinate.In general, can reach more than 95% by the resulting purity of rectificating method of the present invention t-butyl catechol.
In to the t-butyl catechol raffinate impurity more after a little while, the resulting purity to t-butyl catechol of rectifying is higher, can directly be used as stopper, does not need to carry out in aliphatic solvents recrystallization (promptly this moment, the aliphatic hydrocarbon consumption was 0) again.
Impurity is more in to the t-butyl catechol raffinate, especially contains to be difficult in rectifying separately and during the impurity that removes, rectifying is resulting low slightly to t-butyl catechol purity, perhaps often has darker color, is unsuitable for direct use.In this case, can t-butyl catechol be dissolved in the said aliphatic solvents in front rectifying is resulting, and under 15～30 ℃, carry out recrystallization.The consumption of aliphatic hydrocarbon is for needing 0.5～10 times (by weight) to the t-butyl catechol amount of recrystallization.Refilter behind the recrystallization and can obtain white or peach its purity can reach 95.0～99.9% to the crystallization of t-butyl catechol powdery, fusing point can be used as stopper more than 52 ℃.
By recrystallization and filter the back gained to the crystallization of t-butyl catechol powdery, generally can not make drying treatment, but if necessary, also can carry out drying being no more than under 45 ℃ the temperature.
According to handled difference to impurity composition and content in the t-butyl catechol raffinate, can be different by the yield that method of the present invention reclaimed to t-butyl catechol, generally can be 50～90%.
Can be according to method of the present invention from highly purified to t-butyl catechol to reclaiming the t-butyl catechol raffinate, its fusing point reaches more than 52 ℃, can be used as the stopper of polymerization single polymerization monomer, and recycling use and do not have bad influence repeatedly.Since method of the present invention realized recycling price higher to t-butyl catechol, therefore have tangible economic benefit.
The present invention is described in further detail below in conjunction with embodiment:
Embodiment 1
To the content to t-butyl catechol in the t-butyl catechol raffinate is 49%.Get this kind raffinate and under 40mmHg, carry out rectification under vacuum.Removed impurity in the past for 185 ℃ in tower top temperature, and collected the t-butyl catechol cut down at 185 ℃.Tower still temperature finally is 220 ℃.Brown heavy constituent remain in the tower still.
The purity to t-butyl catechol that obtains by rectifying reaches 97%, but has redness.With rectifying obtain t-butyl catechol is dissolved in boiling range is in 60～90 ℃ the petroleum hydrocarbon, and, promptly obtain the powdery crystallization of white after the filtration at 20 ℃ of following recrystallizations, purity is more than 99%.
Embodiment 2
To the content to t-butyl catechol in the t-butyl catechol raffinate is 43%, but wherein with less to the close impurity of t-butyl catechol boiling point.Get this kind raffinate and under 60mmHg, carry out rectification under vacuum.Removed impurity in the past for 190 ℃ in tower top temperature, collected the t-butyl catechol cut down at 190 ℃.Tower still temperature finally is 230 ℃.
The purity to t-butyl catechol that obtains by rectifying is 98.2%.With rectifying obtain t-butyl catechol is dissolved in boiling range is in 60～90 ℃ the petroleum hydrocarbon, and, promptly obtain white powdery crystallization after the filtration at 20 ℃ of following recrystallizations, purity is more than 99%.
Embodiment 3
To containing more and close to t-butyl catechol boiling point impurity in the t-butyl catechol raffinate, as methyl tertiary butyl phenol, diisopropyl phenol, 2,4-di-tert-butyl phenol, front three naphthalene, adjacent withered
Phenol, withered
Phenol, to withered
Phenol, tertiary butyl methoxyl group phenol etc.Get this kind raffinate and carry out rectification under vacuum under 20mmHg, control of reflux ratio is about 5.Removed impurity in the past for 170 ℃ in tower top temperature, collected the t-butyl catechol cut down at 170 ℃.Tower still temperature finally is 200 ℃.
The purity to t-butyl catechol that obtains by rectifying is 98.2%.With rectifying obtain t-butyl catechol is dissolved in boiling range is in 60～90 ℃ the petroleum hydrocarbon, and, promptly obtain the powdery crystallization of white after the filtration at 20 ℃ of following recrystallizations, purity is more than 99%.
Embodiment 4
To the t-butyl catechol raffinate with embodiment 1.Get this kind raffinate and carry out atmospheric distillation earlier, remove boiling point, under 40mmHg, carry out rectification under vacuum then at the light constituent impurity below 150 ℃.Removed impurity in the past for 185 ℃ in tower top temperature, and collected the t-butyl catechol cut down at 185 ℃.With what rectifying obtained t-butyl catechol is carried out recrystallization in boiling range is 60～90 ℃ petroleum hydrocarbon, promptly obtain the powdery crystallization of white after the filtration, purity is more than 99%.
Embodiment 5
To t-butyl catechol raffinate and distillation operation condition and process all with embodiment 2.
With rectifying obtains t-butyl catechol is dissolved in the hexane, the hexane consumption is identical with the amount to t-butyl catechol that needs recrystallization.At 20 ℃ of following recrystallizations, filtration also gets white powdery crystallization after 40～45 ℃ of following dryings, and its purity is 99.5%, and fusing point is 53 ℃.
Embodiment 6
To t-butyl catechol raffinate and distillation operation condition and process all with embodiment 2.
With rectifying obtains t-butyl catechol is dissolved in the heptane, the heptane consumption is identical to the amount of t-butyl catechol with the requirement crystalline.At 20 ℃ of following recrystallizations, filter also 40～45 ℃ dry down, the gained result is identical with embodiment 5, only its rate of drying slower than embodiment 5.
Embodiment 7
To the content to t-butyl catechol in the t-butyl catechol raffinate is 85%.Get this kind raffinate and under 40mmHg, carry out rectification under vacuum.Removed impurity in the past for 185 ℃ in tower top temperature, and collected the t-butyl catechol cut down at 185 ℃.Heavy constituent remain in the tower still.
The purity to t-butyl catechol that obtains by rectifying reaches more than 98%, can directly be used as stopper, and not need to carry out recrystallization again.
Reference examples 1
To the t-butyl catechol raffinate with embodiment 7.Get this kind raffinate and carry out simple underpressure distillation.The purity to t-butyl catechol of distillation gained does not improve.That gets the distillation gained carries out recrystallization to t-butyl catechol in boiling range is 60～90 ℃ petroleum hydrocarbon, recrystallization temperature does not still have crystallization to separate out when reducing to 0～-5 ℃.
Embodiment 8
To t-butyl catechol raffinate, distillation operation condition and process and recrystallization operational condition and process all with embodiment 1.The sodium bisulfite of adding 1% in rectifying (by the raw material weight that drops into), the result of gained is identical with embodiment 1.
Claims (30)
1, a kind of adopt intermittently or method to t-butyl catechol is reclaimed in continuous rectification is characterized in that absolute pressure is that environmental stress (is generally 1.013x10 in tower still temperature is 80～260 ℃, tower
5Pa)～1.333x10
4Pa (promptly will carry out normal rectification under vacuum to the t-butyl catechol raffinate under 760～100mmHg), remove the impurity below the t-butyl catechol boiling point, and absolute pressure be 1.333x10 in tower
4～2.666x10
3Pa (promptly proceeds rectification under vacuum under 100～20mmHg), collecting the t-butyl catechol cut under with selected pressure is corresponding the t-butyl catechol boiling point, the heavy component of t-butyl catechol is discharged at the bottom of tower, can add 0～2% sodium bisulfite (by the raw material weight that drops into) in the rectifying, control of reflux ratio is in 1～20% scope in the rectifying.
2,, it is characterized in that absolute pressure is that environmental stress (is generally 1.013x10 in tower according to the said method of claim 1
5Pa is 760mmHg) under carry out atmospheric distillation, remove the light constituent impurity that boiling point is lower than 150 ℃, and then at 1.333x10
4～2.666x10
3Pa(carries out rectification under vacuum under 100～20mmHg), removes the impurity below the t-butyl catechol boiling point.
3,, it is characterized in that absolute pressure is 1.333x10 in tower according to the said method of claim 1
4～2.666x10
3Pa(directly carries out rectification under vacuum under 100～20mmHg), removes the impurity below the t-butyl catechol boiling point.
4, according to the said method of one of claim 1～3, it is characterized in that tower still temperature is 80～240 ℃, optimum temps is 80～220 ℃.
5,, it is characterized in that the absolute pressure in the tower is 7.998x10 when rectification under vacuum according to the said method of one of claim 1～3
3～2.666x10
3Pa(is 60～20mmHg), is preferably 5.322x10
3～2.666x10
3Pa(is 40～20mmHg).
6,, it is characterized in that the absolute pressure in the tower is 7.998x10 when rectification under vacuum according to the said method of claim 4
3～2.666x10
3Pa(is 60～20mmHg), is preferably 5.322x10
3～2.666x10
3Pa(is 40～20mmHg).
7, according to the said method of one of claim 1～3, it is characterized in that down collected being carried out recrystallization to t-butyl catechol in aliphatic solvents at 15～30 ℃, in said aliphatic hydrocarbon aromaticity content be 0～10%(by weight), cycloalphatic hydrocarbon content be 0～50%(by weight), the consumption of aliphatic solvents is for needing 0.5～10 times (by weight) to the t-butyl catechol amount of recrystallization.
8, according to the said method of claim 4, it is characterized in that down collected being carried out recrystallization to t-butyl catechol in aliphatic solvents at 15～30 ℃, in said aliphatic hydrocarbon aromaticity content be 0～10%(by weight), cycloalphatic hydrocarbon content be 0～50%(by weight), the consumption of aliphatic solvents is for needing 0.5～10 times (by weight) to the t-butyl catechol amount of recrystallization.
9, according to the said method of claim 5, it is characterized in that down collected being carried out recrystallization to t-butyl catechol in aliphatic solvents at 15～30 ℃, in said aliphatic hydrocarbon aromaticity content be 0～10%(by weight), cycloalphatic hydrocarbon content be 0～50%(by weight), the consumption of aliphatic solvents is for needing 0.5～10 times (by weight) to the t-butyl catechol amount of recrystallization.
10, according to the said method of claim 6, it is characterized in that down collected being carried out recrystallization to t-butyl catechol in aliphatic solvents at 15～30 ℃, in said aliphatic hydrocarbon aromaticity content be 0～10%(by weight), cycloalphatic hydrocarbon content be 0～50%(by weight), the consumption of aliphatic solvents is for needing 0.5～10 times (by weight) to the t-butyl catechol amount of recrystallization.
11,, it is characterized in that said aliphatic hydrocarbon is the aliphatic hydrocarbon that contains 5 to 12 carbon atoms according to the said method of claim 7.
12,, it is characterized in that said aliphatic hydrocarbon is the aliphatic hydrocarbon that contains 5 to 12 carbon atoms according to the said method of claim 8.
13,, it is characterized in that said aliphatic hydrocarbon is the aliphatic hydrocarbon that contains 5 to 12 carbon atoms according to the said method of claim 9.
14,, it is characterized in that said aliphatic hydrocarbon is the aliphatic hydrocarbon that contains 5 to 12 carbon atoms according to the said method of claim 10.
15,, it is characterized in that the said aliphatic hydrocarbon that contains 5 to 12 carbon atoms is hexane or heptane according to the said method of claim 11.
16,, it is characterized in that the said aliphatic hydrocarbon that contains 5 to 12 carbon atoms is hexane or heptane according to the said method of claim 12.
17,, it is characterized in that the said aliphatic hydrocarbon that contains 5 to 12 carbon atoms is hexane or heptane according to the said method of claim 13.
18,, it is characterized in that the said aliphatic hydrocarbon that contains 5 to 12 carbon atoms is hexane or heptane according to the said method of claim 14.
19,, it is characterized in that said aliphatic hydrocarbon is the mixing-in fat hydrocarbon that contains 5 to 12 carbon atoms according to the said method of claim 7.
20,, it is characterized in that said aliphatic hydrocarbon is the mixing-in fat hydrocarbon that contains 5 to 12 carbon atoms according to the said method of claim 8.
21,, it is characterized in that said aliphatic hydrocarbon is the mixing-in fat hydrocarbon that contains 5 to 12 carbon atoms according to the said method of claim 9.
22,, it is characterized in that said aliphatic hydrocarbon is the mixing-in fat hydrocarbon that contains 5 to 12 carbon atoms according to the said method of claim 10.
23,, it is characterized in that the said mixing-in fat hydrocarbon that contains 5 to 12 carbon atoms is that boiling range is 40～120 ℃ a petroleum hydrocarbon according to the said method of claim 19.
24,, it is characterized in that the said mixing-in fat hydrocarbon that contains 5 to 12 carbon atoms is that boiling range is 40～120 ℃ a petroleum hydrocarbon according to the said method of claim 20.
25,, it is characterized in that the said mixing-in fat hydrocarbon that contains 5 to 12 carbon atoms is that boiling range is 40～120 ℃ a petroleum hydrocarbon according to the said method of claim 21.
26,, it is characterized in that the said mixing-in fat hydrocarbon that contains 5 to 12 carbon atoms is that boiling range is 40～120 ℃ a petroleum hydrocarbon according to the said method of claim 22.
27,, it is characterized in that the said mixing-in fat hydrocarbon that contains 5 to 12 carbon atoms is the mixed alkanes of 5 to 9 carbon atoms, or boiling range is 60～90 ℃ a petroleum hydrocarbon according to the said method of claim 19.
28,, it is characterized in that the said mixing-in fat hydrocarbon that contains 5 to 12 carbon atoms is the mixed alkanes of 5 to 9 carbon atoms, or boiling range is 60～90 ℃ a petroleum hydrocarbon according to the said method of claim 20.
29,, it is characterized in that the said mixing-in fat hydrocarbon that contains 5 to 12 carbon atoms is the mixed alkanes of 5 to 9 carbon atoms, or boiling range is 60～90 ℃ a petroleum hydrocarbon according to the said method of claim 21.
30,, it is characterized in that the said mixing-in fat hydrocarbon that contains 5 to 12 carbon atoms is the mixed alkanes of 5 to 9 carbon atoms, or boiling range is 60～90 ℃ a petroleum hydrocarbon according to the said method of claim 22.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 88103370 CN1024098C (en) | 1988-06-15 | 1988-06-15 | Process of para-tertiary butyl catechol recovery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 88103370 CN1024098C (en) | 1988-06-15 | 1988-06-15 | Process of para-tertiary butyl catechol recovery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1031524A CN1031524A (en) | 1989-03-08 |
| CN1024098C true CN1024098C (en) | 1994-03-30 |
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ID=4832571
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| CN 88103370 Expired - Fee Related CN1024098C (en) | 1988-06-15 | 1988-06-15 | Process of para-tertiary butyl catechol recovery |
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| CN103562169B (en) * | 2011-06-13 | 2016-04-20 | Fmc有限公司 | The purification process of p-methylallyl pyrocatechol |
| CN103333053B (en) * | 2013-07-09 | 2015-03-11 | 湖南海利株洲精细化工有限公司 | Recovery method of 4-tert-butylcatechol raffinate |
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