CN109535063A - A kind of technique that high-purity carbazole is extracted from carbolineum using integrated separation method - Google Patents
A kind of technique that high-purity carbazole is extracted from carbolineum using integrated separation method Download PDFInfo
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- CN109535063A CN109535063A CN201910034535.3A CN201910034535A CN109535063A CN 109535063 A CN109535063 A CN 109535063A CN 201910034535 A CN201910034535 A CN 201910034535A CN 109535063 A CN109535063 A CN 109535063A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D209/00—Heterocyclic compounds containing five-membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom
- C07D209/56—Ring systems containing three or more rings
- C07D209/80—[b, c]- or [b, d]-condensed
- C07D209/82—Carbazoles; Hydrogenated carbazoles
- C07D209/84—Separation, e.g. from tar; Purification
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Abstract
The present invention relates to a kind of techniques that high-purity carbazole is extracted from carbolineum using integrated separation method, comprising: 1) high-pressure hydrogenation kettle is added in raw material carbolineum fraction and catalyst and carries out hydrogenation reaction；2) reaction solution is filtered, recycles catalyst, filtrate directly cooling obtains carbazole product；Or filtrate isolates the light fraction including hydrogenation anthracene, hydrogenation including luxuriant and rich with fragrance by vacuum distillation/air-distillation, dissolves by heating after remaining kettle liquid addition solvent one and cools down again, is recrystallized to give carbazole product；3) high-purity carbazole that purity is greater than 98.5% is obtained after the carbazole product obtained is vacuum dried.The present invention by effectively reducing the boiling point and fusing point of separation component to carbolineum fraction selective hydrogenation, by be simply evaporated under reduced pressure/air-distillation may separate out the hydrogenation products such as anthracene, phenanthrene, remaining carbazole pregnant solution obtains high-purity carbazole product by crystallisation；Solves the problems such as process flow during traditional carbazole separation and Extraction is complicated, energy consumption is high, environmental pollution is serious.
Description
Technical field
The present invention relates to coal tar separation technology fields more particularly to a kind of use integrated separation method, and height is extracted from carbolineum
The technique of pure carbazole.
Background technique
Carbolineum is very important fraction during coal tar distillation, and main component is anthracene, phenanthrene and carbazole, content difference
For 4-7%, 10-15% and 5-8%.Carbolineum fraction is processed, it is former that the important polycyclic aromatic hydrocarbon such as carbazole, anthracene can be obtained
Material, wherein carbazole is the important source material for producing dyestuff, plastics and pesticide, and early existing industrial production, only scale is much smaller than essence
Anthracene, the usually byproduct as anthracene production.Carbazole is a kind of nitrogen-containing heterocycle compound, is economical price highest in coal tar
One of ingredient, most of carbazole in the world is extract from coal tar.In recent years, due to photoelectric material, conjunction
Constantly increase at the demand of the emerging fields such as resin, the market price of carbazole is much higher than anthracene, becomes coal tar processing corporate boss
The profit growth point wanted.
The conventional production process of carbazole has sulfuric acid process, solvent method, fused junction crystallization and rectification under vacuum method, and wherein sulfuric acid process has been
It is eliminated, manufacturing enterprise, China mainly uses solvent extraction law technology in addition to using vacuum distillation technique at present.Solvent extraction
With " new method of a kind of refined anthracene, phenanthrene and carbazole " (the patent publication No. CN1l21103A) of Beijing combustion gas coal chemical industry research institute
(number of patent application is with " a kind of method of purification of coal tar naphtha carbazole " of Shanxi Yongdong Chemical Co., Ltd.
It CN201410415342.X is) representative, using the anthracene of the direct high-purity of the mixed extractant solvent precipitation method, carbazole, the technique
Haveing the shortcomings that solvent usage is big, repeats crystallization causes energy consumption high.And it is evaporated in vacuo with fusion-crystallization technology respectively with Qujing crowd
(number of patent application is " method that mixing carbolineum extracts fluorenes, anthracene and carbazole " of one fine chemistry industry limited liability company
) and " anthracene and carbazole are prepared by fusion-crystallization " of Rategers VFT AG CN201010114548.0
(number of patent application CN02804079.1) is representative, technologically advanced, and product purity is high, and it is current industry that " three wastes " are few
Developing direction.But since the boiling point of anthracene, phenanthrene and carbazole differs smaller (respectively 340 DEG C, 338.4 DEG C and 354.76 DEG C), and
Fusing point is at 100 DEG C~250 DEG C, and wherein the fusing point of carbazole and anthracene is more closely, cause vacuum distillation and fusion-crystallization technology to deposit
The problems such as process conditions require harshness, and energy consumption is high, equipment investment is high.
Summary of the invention
The present invention provides a kind of techniques for extracting high-purity carbazole from carbolineum using integrated separation method, by evaporating carbolineum
Component selections add hydrogen, effectively reduce the boiling point and fusing point of separation component, by be simply evaporated under reduced pressure/air-distillation can divide
The hydrogenation products such as anthracene, phenanthrene are separated out, remaining carbazole pregnant solution obtains high-purity carbazole product by crystallisation；The present invention solves tradition
The problems such as process flow is complicated during carbazole separation and Extraction, energy consumption is high, environmental pollution is serious.
In order to achieve the above object, the present invention is implemented with the following technical solutions:
A kind of technique for being extracted high-purity carbazole from carbolineum using integrated separation method, is included the following steps:
1) raw material carbolineum fraction and catalyst are added in high-pressure hydrogenation kettle and carry out hydrogenation reaction；
2) reaction solution for obtaining step 1) filters, and recycles catalyst, and filtrate directly cooling obtains carbazole product；Or filtrate
The light fraction including hydrogenation anthracene, hydrogenation including luxuriant and rich with fragrance is isolated by vacuum distillation/air-distillation, after solvent one is added in remaining kettle liquid
Heating for dissolving cools down again, is recrystallized to give carbazole product；
3) high-purity carbazole that purity is greater than 98.5% is obtained after the carbazole product that step 2) obtains is vacuum dried.
The raw material carbolineum fraction is a carbolineum, de- brilliant carbolineum or crude anthracene.
Solvent two is additionally added in raw material carbolineum fraction before the step 1) hydrogenation reaction, solvent two includes toluene, diformazan
One or more of benzene, n-butanol, solvent naphtha arbitrarily mix；Solvent two passes through vacuum distillation/normal pressure in step 2)
It is distilled to recover.
The catalyst is activated carbon supported type metallic catalyst or metal oxide supported type metallic catalyst.
The catalyst is the metallic catalyst of activated carbon supported nickel or nickel alloy.
The catalyst is the metallic catalyst of nickel or nickel alloy.
The additional amount of the catalyst is the 10%~30% of raw material carbolineum fraction quality.
Pressure when the step 1) hydrogenation reaction is 1.5~3.0MPa, and reaction temperature is 120~200 DEG C, the reaction time
For 4~10h.
When the step 2) is evaporated under reduced pressure, pressure is 5~10mmHg, and 30~80 DEG C of fractions are recycling design, 80~190 DEG C
Fraction is the light fraction luxuriant and rich with fragrance containing hydrogenation anthracene, hydrogenation.
The solvent one is that one or more of toluene, dimethylbenzene, methanol, ethyl alcohol, normal heptane, DMF are arbitrarily mixed
It closes.
Compared with prior art, the beneficial effects of the present invention are:
1) using reaction integrated separation technology, hydrogenation anthracene and hydrogenation are luxuriant and rich with fragrance to be had compared with low boiling point and fusing point, is easy to logical with carbazole
Distillation separation is crossed, to succinctly and efficiently extract the high added value component carbazole in carbolineum；
2) carbazole that the present invention extracts is high purity product, and capability and performance greatly promotes, and is applicable not only to traditional synthesis dye
Material, pesticide, medicine and other fields, while the products applications requirement such as meet photoelectric material, synthetic resin, market is to emerging high-end neck
Domain extends；
3) the hydrogenation anthracene of by-product of the present invention, hydrogenation phenanthrene etc. can be applied to other hydrogenation reactions directly as hydrogen donor；
4) present invention has equipment investment small, simple process, and equipment corrodes small, environmentally friendly feature.
Detailed description of the invention
Fig. 1 is the monitoring gas chromatogram of hydrogenation process described in the embodiment of the present invention 1.
In figure: 1. unknown materials, 2,3. anthracene, luxuriant and rich with fragrance 4. anthracene of octahydro substituent, 5. tetrahydro carbazole of luxuriant and rich with fragrance tetrahydro substituent, 6. click
Azoles
Specific embodiment
Specific embodiments of the present invention will be further explained with reference to the accompanying drawing:
A kind of technique for being extracted high-purity carbazole from carbolineum using integrated separation method of the present invention, is included the following steps:
1) raw material carbolineum fraction and catalyst are added in high-pressure hydrogenation kettle and carry out hydrogenation reaction；
2) reaction solution for obtaining step 1) filters, and recycles catalyst, and filtrate directly cooling obtains carbazole product；Or filtrate
The light fraction including hydrogenation anthracene, hydrogenation including luxuriant and rich with fragrance is isolated by vacuum distillation/air-distillation, after solvent one is added in remaining kettle liquid
Heating for dissolving cools down again, is recrystallized to give carbazole product；
3) high-purity carbazole that purity is greater than 98.5% is obtained after the carbazole product that step 2) obtains is vacuum dried.
The raw material carbolineum fraction is a carbolineum, de- brilliant carbolineum or crude anthracene.
Solvent two is additionally added in raw material carbolineum fraction before the step 1) hydrogenation reaction, solvent two includes toluene, diformazan
One or more of benzene, n-butanol, solvent naphtha arbitrarily mix；Solvent two passes through vacuum distillation/normal pressure in step 2)
It is distilled to recover.
The catalyst is activated carbon supported type metallic catalyst or metal oxide supported type metallic catalyst.
The catalyst is the metallic catalyst of activated carbon supported nickel or nickel alloy.
The catalyst is the metallic catalyst of nickel or nickel alloy.
The additional amount of the catalyst is the 10%~30% of raw material carbolineum fraction quality.
Pressure when the step 1) hydrogenation reaction is 1.5~3.0MPa, and reaction temperature is 120~200 DEG C, the reaction time
For 4~10h.
When the step 2) is evaporated under reduced pressure, pressure is 5~10mmHg, and 30~80 DEG C of fractions are recycling design, 80~190 DEG C
Fraction is the light fraction luxuriant and rich with fragrance containing hydrogenation anthracene, hydrogenation.
The solvent one is that one or more of toluene, dimethylbenzene, methanol, ethyl alcohol, normal heptane, DMF are arbitrarily mixed
It closes.
Following embodiment is implemented under the premise of the technical scheme of the present invention, gives detailed embodiment and tool
The operating process of body, but protection scope of the present invention is not limited to following embodiments.Method therefor is such as without spy in following embodiments
Not mentionleting alone bright is conventional method.
[embodiment 1]
In the present embodiment, with heating and agitating device, thermometer, reflux condensing tube 500mL autoclave in, investment
100g crude anthracene (carbazole mass content is 16.5%), dimethylbenzene 400mL, activated carbon supported Raney nickel 20g, nitrogen displacement is for several times
Afterwards, it in 2.0~2.5Mpa of Hydrogen Vapor Pressure, 140~170 DEG C of reaction temperature, reacts under conditions of 3000 turns/min of agitation revolution, instead
5h between seasonable is cooled to 70~80 DEG C after stopping reaction, filters out catalyst, obtain filtrate.
The present embodiment hydrogenation process monitoring gas chromatogram is as shown in Figure 1,1 represent unknown materials in figure, 2,3 represent
Anthracene, luxuriant and rich with fragrance octahydro substituent, 4 represent anthracene, luxuriant and rich with fragrance tetrahydro substituent, and 5 represent tetrahydro carbazole, and 6 represent carbazole.
Obtained filtrate is evaporated under reduced pressure, under the pressure of 10mmHg, collects 80 DEG C or less fraction, that is, recycling designs,
Then proceed to collect the hydrogenation products of 190 DEG C or less fraction i.e. anthracenes, phenanthrene etc..
Dimethylbenzene 50mL is added into remaining kettle liquid, is heated to return stirring 0.5h, filtering removal solid impurity, filtrate is delayed
Slowly 20~25 DEG C of crystallizations are cooled to, solid carbazole is obtained by filtration, is dried in vacuo 6h or more, product gas phase content at 100 DEG C
99.11%, weight 15.3g, yield is about 94.6%.
[embodiment 2]
In the present embodiment, with heating and agitating device, thermometer, reflux condensing tube 500ml autoclave in, investment
A carbolineum (carbazole mass content be 8.5%) of 200g, dimethylbenzene 400ml, activated carbon supported Raney nickel 40g, nitrogen displacement
It is 140~150 DEG C of reaction temperature, anti-under conditions of 3000 turns/min of agitation revolution in 2.0~2.5Mpa of Hydrogen Vapor Pressure after for several times
It answers, the reaction time is about 7h, is cooled to 70~80 DEG C after stopping reaction, filters out catalyst, obtain hydrogenation products.
Obtained hydrogenation products are evaporated under reduced pressure, under the pressure of 10mmHg, 80 DEG C or less fractions is collected and recycles
Solvent then proceedes to the hydrogenation products for collecting 190 DEG C or less fraction i.e. anthracenes, phenanthrene etc..
Dimethylbenzene 50mL is added into remaining kettle liquid, is heated to return stirring 0.5h, filtering removal solid impurity, filtrate is delayed
Slowly 20~25 DEG C of crystallizations are cooled to, carbazole product is obtained by filtration, is dried in vacuo 6h or more, product gas phase content at 100 DEG C
99.2%, weight 14.8g, yield is about 87%.
[embodiment 3]
In the present embodiment, with heating and agitating device, thermometer, reflux condensing tube 500ml autoclave in, investment
The crude anthracene (carbazole mass content be 16.5%) of 100g, dimethylbenzene 400ml, activated carbon supported Raney nickel 10g, nitrogen displacement number
After secondary, in 2.0~2.5Mpa of Hydrogen Vapor Pressure, 150~170 DEG C of reaction temperature, react under conditions of 3000 turns/min of agitation revolution,
Reaction time is about 10h, is cooled to 70~80 DEG C after stopping reaction, filters out catalyst, obtain filtrate.
Obtained filtrate is evaporated under reduced pressure, under the pressure of 10mmHg, collects 80 DEG C or less fraction, that is, recycling designs,
Then proceed to collect the hydrogenation products of 190 DEG C or less fraction i.e. anthracenes, phenanthrene etc..
Dimethylbenzene 50mL is added into remaining kettle liquid, is heated to return stirring 0.5h, filtering removal solid impurity, filtrate is delayed
Slowly 20~25 DEG C of crystallizations are cooled to, carbazole product is obtained by filtration, is dried in vacuo 6h or more, product gas phase content at 100 DEG C
98.5%, weight 14.1g, yield 84.5%.
[embodiment 4]
In the present embodiment, with heating and agitating device, thermometer, reflux condensing tube 500ml autoclave in, investment
A carbolineum (carbazole mass content be 8.5%) of 200g, dimethylbenzene 400ml, activated carbon supported Raney nickel 40g, nitrogen displacement
It is 140~150 DEG C of reaction temperature, anti-under conditions of 3000 turns/min of agitation revolution in 2.0~2.5Mpa of Hydrogen Vapor Pressure after for several times
It answers, the reaction time is about 7h, is cooled to 70~80 DEG C after stopping reaction, filters out catalyst, obtain filtrate.
Obtained filtrate is continued cool to 20~25 DEG C, 2h or more is crystallized, filters to isolate carbazole product, vacuum 100
DEG C drying 6h or more, product gas phase content 99.38%, weight 11.2g, yield is about 65.8%.Remaining mother liquor is anthracene, phenanthrene etc.
Hydrogenation products.
To sum up, the present invention, can be safe by reaction integrated separation technology, simply extracts from coal tar carbolineum fraction
High-purity carbazole, product can meet the application requirement in the fields such as optical material, while the hydrogenation products of by-product can be used as hydrogen donor and answer
For other hydrogenation reactions.Economy with higher is suitable for large-scale production.
The foregoing is only a preferred embodiment of the present invention, but scope of protection of the present invention is not limited thereto,
Anyone skilled in the art in the technical scope disclosed by the present invention, according to the technique and scheme of the present invention and its
Inventive concept is subject to equivalent substitution or change, should be covered by the protection scope of the present invention.
Claims (10)
1. a kind of technique for extracting high-purity carbazole from carbolineum using integrated separation method, which comprises the steps of:
1) raw material carbolineum fraction and catalyst are added in high-pressure hydrogenation kettle and carry out hydrogenation reaction；
2) reaction solution for obtaining step 1) filters, and recycles catalyst, and filtrate directly cooling obtains carbazole product；Or filtrate passes through
The light fraction including hydrogenation anthracene, hydrogenation including luxuriant and rich with fragrance is isolated in vacuum distillation/air-distillation, and remaining kettle liquid heats after solvent one is added
Dissolution cools down again, is recrystallized to give carbazole product；
3) high-purity carbazole that purity is greater than 98.5% is obtained after the carbazole product that step 2) obtains is vacuum dried.
2. a kind of technique for extracting high-purity carbazole from carbolineum using integrated separation method according to claim 1, feature
It is, the raw material carbolineum fraction is a carbolineum, de- brilliant carbolineum or crude anthracene.
3. a kind of technique for extracting high-purity carbazole from carbolineum using integrated separation method according to claim 1, feature
Be, be additionally added solvent two in the raw material carbolineum fraction before the step 1) hydrogenation reaction, solvent two include toluene, dimethylbenzene,
One or more of n-butanol, solvent naphtha arbitrarily mix；Solvent two passes through vacuum distillation/air-distillation in step 2)
Recycling.
4. a kind of technique for extracting high-purity carbazole from carbolineum using integrated separation method according to claim 1, feature
It is, the catalyst is activated carbon supported type metallic catalyst or metal oxide supported type metallic catalyst.
5. a kind of technique for extracting high-purity carbazole from carbolineum using integrated separation method according to claim 1 or 4, special
Sign is that the catalyst is the metallic catalyst of activated carbon supported nickel or nickel alloy.
6. a kind of technique for extracting high-purity carbazole from carbolineum using integrated separation method according to claim 1 or 4, special
Sign is that the catalyst is the metallic catalyst of nickel or nickel alloy.
7. a kind of technique for extracting high-purity carbazole from carbolineum using integrated separation method according to claim 1 or 4, special
Sign is that the additional amount of the catalyst is the 10%~30% of raw material carbolineum fraction quality.
8. a kind of technique for extracting high-purity carbazole from carbolineum using integrated separation method according to claim 1, feature
It is, pressure when step 1) hydrogenation reaction is 1.5~3.0MPa, and reaction temperature is 120~200 DEG C, the reaction time 4
~10h.
9. a kind of technique for extracting high-purity carbazole from carbolineum using integrated separation method according to claim 1, feature
It is, when the step 2) is evaporated under reduced pressure, pressure is 5~10mmHg, and 30~80 DEG C of fractions are recycling design, and 80~190 DEG C evaporate
It is divided into the light fraction luxuriant and rich with fragrance containing hydrogenation anthracene, hydrogenation.
10. a kind of technique for extracting high-purity carbazole from carbolineum using integrated separation method according to claim 1, feature
It is, the solvent one is that one or more of toluene, dimethylbenzene, methanol, ethyl alcohol, normal heptane, DMF arbitrarily mix.
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| CN1229314C (en) * | 2001-01-24 | 2005-11-30 | 拉特格斯化学公开股份有限公司 | Obtaining anthracene and carbazole by melt-crystallization |
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