CN109535063B - Process for extracting carbazole from anthracene oil by coupling separation method - Google Patents
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- 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
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Abstract
The invention relates to a process for extracting high-purity carbazole from anthracene oil by adopting a coupling separation method, which comprises the following steps: 1) adding the anthracene oil fraction and the catalyst into a high-pressure hydrogenation kettle for hydrogenation reaction; 2) filtering the reaction solution and recovering the catalyst; separating light fractions including hydrogenated anthracene and hydrogenated phenanthrene from the filtrate through reduced pressure distillation/normal pressure distillation, adding a solvent I into the residual kettle liquid, heating for dissolving, cooling, and recrystallizing to obtain a carbazole product; 3) the obtained carbazole product is dried in vacuum to obtain high-purity carbazole with the purity of more than 98.5 percent. According to the invention, the anthracene oil fraction is selectively hydrogenated, so that the boiling point and the melting point of the separated components are effectively reduced, hydrogenation products such as anthracene and phenanthrene can be separated through simple reduced pressure distillation/normal pressure distillation, and the residual carbazole enriched liquid is subjected to a crystallization method to obtain a high-purity carbazole product; solves the problems of complex process flow, high energy consumption, serious environmental pollution and the like in the traditional carbazole separation and extraction process.
Description
Technical Field
The invention relates to the technical field of coal tar separation, in particular to a process for extracting high-purity carbazole from anthracene oil by adopting a coupling separation method.
Background
Anthracene oil is a very important fraction in the distillation process of coal tar, and mainly comprises anthracene, phenanthrene and carbazole with the contents of 4-7%, 10-15% and 5-8%, respectively. The anthracene oil fraction is processed to obtain important polycyclic aromatic hydrocarbon raw materials such as carbazole, refined anthracene and the like, wherein carbazole is an important raw material for producing dyes, plastics and pesticides, has already been industrially produced, is only far smaller than refined anthracene in scale, and is generally used as a byproduct in the refined anthracene production. Carbazole is a nitrogen-containing heterocyclic compound and is one of the most economic and expensive components in coal tar, and most of carbazole in the world is extracted from coal tar. In recent years, due to the increasing demand of new fields such as photoelectric materials, synthetic resins and the like, the market price of carbazole is far higher than that of refined anthracene, and the carbazole becomes a main profit growth point of coal tar processing enterprises.
The conventional production process of carbazole comprises sulfuric acid method, solvent method, melt crystallization method and vacuum rectification method, wherein the sulfuric acid method is eliminated, and the solvent extraction method is mainly adopted in addition to the vacuum distillation technology in the production enterprises in China at present. The solvent extraction method is represented by a new method for refining anthracene, phenanthrene and carbazole of Beijing gas coal chemical research institute (the patent publication number is CN1l21103A) and a method for purifying coal tar refined carbazole of Shanxi Yongdong chemical corporation (the patent application number is CN201410415342.X), and adopts a mixed solvent extraction precipitation method to directly prepare high-purity anthracene and carbazole. The vacuum distillation and melt crystallization technologies are represented by a method for extracting fluorene, anthracene and carbazole from mixed anthracene oil of the fine chemical industry, Inc. (with the patent application number of CN201010114548.0) and a method for preparing anthracene and carbazole through melt crystallization, which are disclosed by the Laterge chemical publication, Inc. (with the patent application number of CN02804079.1), respectively, the technology is advanced, the product purity is high, and the three wastes are few, so that the method is the current industry development direction. However, the boiling points of anthracene, phenanthrene and carbazole are different slightly (340 ℃, 338.4 ℃ and 354.76 ℃) and the melting points are all 100-250 ℃, wherein the melting points of carbazole and anthracene are closer, so that the vacuum distillation and melt crystallization technologies have the problems of harsh technological condition requirements, high energy consumption, high equipment investment and the like.
Disclosure of Invention
The invention provides a process for extracting high-purity carbazole from anthracene oil by adopting a coupling separation method, which effectively reduces the boiling point and the melting point of separated components by selectively hydrogenating anthracene oil fractions, can separate hydrogenation products such as anthracene and phenanthrene by simple reduced pressure distillation/normal pressure distillation, and obtains a high-purity carbazole product from residual carbazole enriched liquid by a crystallization method; the invention solves the problems of complex process flow, high energy consumption, serious environmental pollution and the like in the traditional carbazole separation and extraction process.
In order to achieve the purpose, the invention adopts the following technical scheme:
a process for extracting high-purity carbazole from anthracene oil by coupling separation method comprises the following steps:
1) adding the anthracene oil fraction and the catalyst into a high-pressure hydrogenation kettle for hydrogenation reaction; the raw material anthracene oil fraction is anthracene oil, decrystallized anthracene oil or crude anthracene.
2) Filtering the reaction liquid obtained in the step 1), and recovering the catalyst; separating light fractions including hydrogenated anthracene and hydrogenated phenanthrene from the filtrate through reduced pressure distillation/normal pressure distillation, adding a solvent I into the residual kettle liquid, heating for dissolving, cooling, and recrystallizing to obtain a carbazole product;
3) and (3) drying the carbazole product obtained in the step 2) in vacuum to obtain high-purity carbazole with the purity of more than 98.5%.
Adding a second solvent into the anthracene oil fraction of the raw material before the hydrogenation reaction in the step 1), wherein the second solvent comprises one or more than two of toluene, xylene, n-butanol and solvent oil which are mixed randomly; the second solvent is recovered in step 2) by distillation under reduced pressure/distillation under atmospheric pressure.
The catalyst is an activated carbon supported metal catalyst or a metal oxide supported metal catalyst.
The catalyst is a metal catalyst of active carbon supported nickel or nickel alloy.
The catalyst is a metal catalyst of nickel or nickel alloy loaded on alumina.
The addition amount of the catalyst is 10-30% of the mass of the anthracene oil fraction serving as the raw material.
The pressure in the hydrogenation reaction in the step 1) is 1.5-3.0 MPa, the reaction temperature is 120-200 ℃, and the reaction time is 4-10 h.
And in the step 2), during reduced pressure distillation, the pressure is 5-10 mmHg, the fraction at 30-80 ℃ is the recovered solvent, and the fraction at 80-190 ℃ is the light fraction containing hydrogenated anthracene and hydrogenated phenanthrene.
The first solvent is one or a mixture of more than two of toluene, xylene, methanol, ethanol, n-heptane and DMF.
Compared with the prior art, the invention has the beneficial effects that:
1) by adopting a reaction coupling separation technology, the hydrogenated anthracene and the hydrogenated phenanthrene have lower boiling points and melting points, and are easy to separate from carbazole through distillation, so that carbazole which is a high value-added component in anthracene oil is simply and efficiently extracted;
2) the carbazole extracted by the method is a high-purity product, the quality and performance are greatly improved, the carbazole is not only suitable for the fields of traditional synthetic dyes, pesticides, medicines and the like, but also meets the application requirements of products such as photoelectric materials, synthetic resins and the like, and the market extends to the emerging high-end field;
3) the by-product hydrogenated anthracene, hydrogenated phenanthrene and the like can be directly used as hydrogen donors to be applied to other hydrogenation reactions;
4) the method has the characteristics of small equipment investment, simple process, small equipment corrosion and environmental friendliness.
Drawings
FIG. 1 is a gas chromatogram for monitoring the hydrogenation reaction process as described in example 1 of the present invention.
In the figure: 1. unknown substances 2,3, anthracene, phenanthrene octahydro substituent 4, anthracene, phenanthrene tetrahydro substituent 5, tetrahydrocarbazole 6, carbazole
Detailed Description
The following further describes embodiments of the present invention with reference to the accompanying drawings:
the invention relates to a process for extracting high-purity carbazole from anthracene oil by adopting a coupling separation method, which comprises the following steps:
1) adding the anthracene oil fraction and the catalyst into a high-pressure hydrogenation kettle for hydrogenation reaction; the raw material anthracene oil fraction is anthracene oil, decrystallized anthracene oil or crude anthracene.
2) Filtering the reaction liquid obtained in the step 1), and recovering the catalyst; separating light fractions including hydrogenated anthracene and hydrogenated phenanthrene from the filtrate through reduced pressure distillation/normal pressure distillation, adding a solvent I into the residual kettle liquid, heating for dissolving, cooling, and recrystallizing to obtain a carbazole product;
3) and (3) drying the carbazole product obtained in the step 2) in vacuum to obtain high-purity carbazole with the purity of more than 98.5%.
Adding a second solvent into the anthracene oil fraction of the raw material before the hydrogenation reaction in the step 1), wherein the second solvent comprises one or more than two of toluene, xylene, n-butanol and solvent oil which are mixed randomly; the second solvent is recovered in step 2) by distillation under reduced pressure/distillation under atmospheric pressure.
The catalyst is an activated carbon supported metal catalyst or a metal oxide supported metal catalyst.
The catalyst is a metal catalyst of active carbon supported nickel or nickel alloy.
The catalyst is a metal catalyst of nickel or nickel alloy loaded on alumina.
The addition amount of the catalyst is 10-30% of the mass of the anthracene oil fraction serving as the raw material.
The pressure in the hydrogenation reaction in the step 1) is 1.5-3.0 MPa, the reaction temperature is 120-200 ℃, and the reaction time is 4-10 h.
And in the step 2), during reduced pressure distillation, the pressure is 5-10 mmHg, the fraction at 30-80 ℃ is the recovered solvent, and the fraction at 80-190 ℃ is the light fraction containing hydrogenated anthracene and hydrogenated phenanthrene.
The first solvent is one or a mixture of more than two of toluene, xylene, methanol, ethanol, n-heptane and DMF.
The following examples are carried out on the premise of the technical scheme of the invention, and detailed embodiments and specific operation processes are given, but the scope of the invention is not limited to the following examples. The methods used in the following examples are conventional methods unless otherwise specified.
[ example 1 ]
In the embodiment, 100g of crude anthracene (the mass content of carbazole is 16.5%), 400mL of xylene and 20g of activated carbon-supported nickel catalyst are put into a 500mL autoclave with a heating and stirring device, a thermometer and a reflux condenser tube, and after nitrogen replacement is carried out for several times, the crude anthracene and the activated carbon-supported nickel catalyst react under the conditions that the hydrogen pressure is 2.0-2.5 Mpa, the reaction temperature is 140-170 ℃, the stirring revolution is 3000 r/min, the reaction time is 5 hours, the temperature is reduced to 70-80 ℃ after the reaction is stopped, and the catalyst is filtered out to obtain filtrate.
The monitored gas chromatogram of the hydrogenation reaction process in this example is shown in fig. 1, wherein 1 represents unknown substance, 2,3 represent anthracene and phenanthrene octahydro substituent, 4 represents anthracene and phenanthrene tetrahydro substituent, 5 represents tetrahydrocarbazole, and 6 represents carbazole.
And carrying out reduced pressure distillation on the obtained filtrate, collecting fractions below 80 ℃ under the pressure of 10mmHg, namely recovering the solvent, and then continuously collecting fractions below 190 ℃, namely hydrogenation products of anthracene, phenanthrene and the like.
Adding 50mL of dimethylbenzene into the residual kettle liquid, heating to reflux and stirring for 0.5h, filtering to remove solid impurities, slowly cooling the filtrate to 20-25 ℃ for crystallization, filtering to obtain solid carbazole, and vacuum-drying at 100 ℃ for more than 6h to obtain a product with the gas phase content of 99.11%, the weight of 15.3g and the yield of 94.6%.
[ example 2 ]
In the embodiment, 200g of anthracene oil (8.5% by mass of carbazole), 400ml of xylene, 40g of activated carbon-supported nickel catalyst are put into a 500ml autoclave with a heating and stirring device, a thermometer and a reflux condenser tube, nitrogen is replaced for several times, the mixture is reacted under the conditions of hydrogen pressure of 2.0-2.5 Mpa, reaction temperature of 140-150 ℃ and stirring revolution of 3000 r/min, the reaction time is about 7 hours, the temperature is reduced to 70-80 ℃ after the reaction is stopped, and the catalyst is filtered out to obtain a hydrogenation product.
And carrying out reduced pressure distillation on the obtained hydrogenation product, collecting fractions below 80 ℃ under the pressure of 10mmHg, namely recovering the solvent, and continuously collecting fractions below 190 ℃, namely the hydrogenation product of anthracene, phenanthrene and the like.
Adding 50mL of dimethylbenzene into the residual kettle liquid, heating to reflux and stirring for 0.5h, filtering to remove solid impurities, slowly cooling the filtrate to 20-25 ℃ for crystallization, filtering to obtain a carbazole product, and performing vacuum drying at 100 ℃ for more than 6h to obtain the carbazole product with the gas phase content of 99.2%, the weight of 14.8g and the yield of 87%.
[ example 3 ]
In the embodiment, 100g of crude anthracene (the mass content of carbazole is 16.5%), 400ml of xylene, 10g of activated carbon-supported nickel catalyst are put into a 500ml autoclave with a heating and stirring device, a thermometer and a reflux condenser tube, nitrogen is replaced for several times, the crude anthracene and the xylene are reacted under the conditions of hydrogen pressure of 2.0-2.5 Mpa, reaction temperature of 150-170 ℃ and stirring revolution of 3000 r/min, the reaction time is about 10 hours, the temperature is reduced to 70-80 ℃ after the reaction is stopped, and the catalyst is filtered out to obtain filtrate.
And carrying out reduced pressure distillation on the obtained filtrate, collecting fractions below 80 ℃ under the pressure of 10mmHg, namely recovering the solvent, and then continuously collecting fractions below 190 ℃, namely hydrogenation products of anthracene, phenanthrene and the like.
Adding 50mL of dimethylbenzene into the residual kettle liquid, heating to reflux and stirring for 0.5h, filtering to remove solid impurities, slowly cooling the filtrate to 20-25 ℃ for crystallization, filtering to obtain a carbazole product, and performing vacuum drying at 100 ℃ for more than 6h to obtain a carbazole product with the gas phase content of 98.5%, the weight of 14.1g and the yield of 84.5%.
[ example 4 ]
In the embodiment, 200g of anthracene oil (8.5% by mass of carbazole), 400ml of xylene, 40g of activated carbon-supported nickel catalyst are put into a 500ml autoclave with a heating and stirring device, a thermometer and a reflux condenser tube, nitrogen is replaced for several times, the mixture is reacted under the conditions of hydrogen pressure of 2.0-2.5 Mpa, reaction temperature of 140-150 ℃ and stirring revolution of 3000 r/min, the reaction time is about 7 hours, the temperature is reduced to 70-80 ℃ after the reaction is stopped, and the catalyst is filtered to obtain filtrate.
And continuously cooling the obtained filtrate to 20-25 ℃, crystallizing for more than 2 hours, filtering and separating out a carbazole product, drying for more than 6 hours at 100 ℃ in vacuum, wherein the gas phase content of the product is 99.38%, the weight of the product is 11.2g, and the yield is about 65.8%. The residual mother liquor is the hydrogenation products of anthracene, phenanthrene and the like.
In conclusion, the method can safely and simply extract high-purity carbazole from coal tar anthracene oil fraction through a reaction coupling separation technology, the product can meet the application requirements in the fields of optical materials and the like, and meanwhile, a byproduct hydrogenation product can be used as a hydrogen donor to be applied to other hydrogenation reactions. Has higher economical efficiency and is suitable for large-scale production.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (9)
1. A process for extracting high-purity carbazole from anthracene oil by a coupling separation method is characterized in that anthracene oil fractions are selectively hydrogenated, the boiling points and the melting points of separation components are reduced, anthracene and phenanthrene hydrogenation products are separated by reduced pressure distillation/atmospheric distillation, and the residual carbazole enriched liquid is subjected to a crystallization method to obtain a high-purity carbazole product; the method specifically comprises the following steps:
1) adding the anthracene oil fraction and the catalyst into a high-pressure hydrogenation kettle for hydrogenation reaction; the raw anthracene oil fraction is anthracene oil, decrystallized anthracene oil or crude anthracene
2) Filtering the reaction liquid obtained in the step 1), and recovering the catalyst; separating light fractions including hydrogenated anthracene and hydrogenated phenanthrene from the filtrate through reduced pressure distillation/normal pressure distillation, adding a solvent I into the residual kettle liquid, heating for dissolving, cooling, and recrystallizing to obtain a carbazole product;
3) and (3) drying the carbazole product obtained in the step 2) in vacuum to obtain high-purity carbazole with the purity of more than 98.5%.
2. The process for extracting high-purity carbazole from anthracene oil by coupling separation method according to claim 1, wherein solvent II is further added to the raw anthracene oil fraction before hydrogenation reaction in step 1), wherein solvent II comprises one or more of toluene, xylene, n-butanol, and solvent oil; the second solvent is recovered in step 2) by distillation under reduced pressure/distillation under atmospheric pressure.
3. The process of claim 1, wherein the catalyst is an activated carbon-supported metal catalyst or a metal oxide-supported metal catalyst.
4. The process for extracting high-purity carbazole from anthracene oil by coupling separation method according to claim 1 or 3, wherein the catalyst is a metal catalyst of nickel or nickel alloy supported on activated carbon.
5. The process for extracting high-purity carbazole from anthracene oil by coupling separation method according to claim 1 or 3, wherein the catalyst is alumina supported nickel or nickel alloy metal catalyst.
6. The process for extracting high-purity carbazole from anthracene oil by using a coupling separation method according to claim 1 or 3, wherein the addition amount of the catalyst is 10-30% of the mass of the raw anthracene oil fraction.
7. The process for extracting high-purity carbazole from anthracene oil by using a coupling separation method according to claim 1, wherein the pressure in the hydrogenation reaction in the step 1) is 1.5-3.0 MPa, the reaction temperature is 120-200 ℃, and the reaction time is 4-10 h.
8. The process for extracting high-purity carbazole from anthracene oil by adopting a coupling separation method according to claim 1, wherein in the step 2), during reduced pressure distillation, the pressure is 5-10 mmHg, the fraction at 30-80 ℃ is a recovered solvent, and the fraction at 80-190 ℃ is a light fraction containing hydrogenated anthracene and hydrogenated phenanthrene.
9. The process of claim 1, wherein the first solvent is one or more selected from toluene, xylene, methanol, ethanol, n-heptane, and DMF.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| DE10103208A1 (en) * | 2001-01-24 | 2002-08-14 | Ruetgers Vft Ag | Obtaining anthracene and carbazole by melt crystallization |
| CN102070511B (en) * | 2009-11-23 | 2014-07-23 | 石其贵 | Method for preparing refined anthracene with content of more than 96 percent and carbazole with content of more than 98 percent |
| CN103205272B (en) * | 2012-01-12 | 2017-03-01 | 易高环保能源研究院有限公司 | High temperature coal-tar produces the method purifying coal tar asphalt |
| CN102703117B (en) * | 2012-06-04 | 2014-07-23 | 神华集团有限责任公司 | Preparation method for diesel oil |
| CN102746103B (en) * | 2012-07-13 | 2014-12-03 | 韩钊武 | Method for preparing refined anthracene by using coal tar as raw material |
| CN103232318B (en) * | 2013-04-16 | 2016-04-06 | 中冶焦耐工程技术有限公司 | With a carbolineum be raw material production anthracene, the method for smart carbazole and luxuriant and rich with fragrance product and device |
| CN103601667B (en) * | 2013-11-30 | 2015-11-18 | 河南城建学院 | A kind of method being separated carbazole from carbolineum |
| CN106995402B (en) * | 2017-02-08 | 2023-05-26 | 兖矿科蓝凯美特化工有限公司 | Equipment for producing fine-carbody and process for producing fine-carbody by utilizing static melting crystallization method |
| CN107162867A (en) * | 2017-04-24 | 2017-09-15 | 邯郸鑫宝煤化能源科技开发有限公司 | It is a kind of to mix the method that carbolineum extracts anthracene and carbazole |
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