CN102070511A - Method for preparing refined anthracene with content of more than 96 percent and carbazole with content of more than 98 percent - Google Patents

Abstract

The invention discloses a method for preparing refined anthracene with content of more than 96 percent and carbazole with content of more than 98 percent. The refined anthracene and the carbazole are deep processed products of coal tar and belong to the technical field of chemical industries. At present, in the production of the carbazole and the refined anthracene in China, the refined anthracene content is only 90 percent, and the carbazole content is only 95 percent. A technical problem to be solved by the invention is that: the refined anthracene content is over 96 percent, and the carbazole content is over 98 percent; in the production process of the carbazole, 8 to 12 times of recrystallization are reduced to 2 times; and yield is increased to 80 percent from 40 percent of the original yield. On the basis of the conventional production process of the carbazole and the refined anthracene in China, two processes of washing crude anthracene with S-100 mother solution to remove phenanthrene with the largest content, and evaporating the crude carbazole are added. A technique of the invention is applied to the deep processing industry of the coal tar.

Description

Content is greater than a kind of manufacture method of 96% anthracene, 98% carbazole

Technical field:

Anthracene, carbazole are the products of coal tar deep processing, and this patent belongs to chemical technology field.

Background technology:

Anthracene, carbazole and phenanthrene belong to polycyclic aromatic hydrocarbons, and anthracene and phenanthrene are isomerss, and a 5-member heterocyclic ring containing nitrogen (pyrrole ring) is arranged in the carbazole structure.They all are high boiling point and high-melting-point hydro carbons, are present in the carbolineum cut of coal tar.Anthracene accounts for 1.2～1.8% in coal tar, and carbazole accounts for 1.5%, and phenanthrene accounts for 4.5～5.0%.They in coal tar be content greater than having accounted for three in 12 compounds of 1.0%, visible its importance in coal tar processing.

Anthracene, carbazole and luxuriant and rich with fragrance boiling point are high and more approaching, and fusing point is also high, are the comparison difficulties so separate.What adopt at present is the solvent wash crystallization process, or distillation and solvent wash crystallization phases bonded method.Industrial scale is generally little, uses interrupter method more.At present the biggest in the world to produce the anthracene device from coal tar be Wa Haimu rolt tar source mill in Duisburg city, Ruhr, Germany, produces 6000 tons per year.

These three main raw materials that compound all is organic chemistry industry, wherein anthracene particularly.No matter from the developing history of dyestuffs industries, still from its realistic situation, anthracene all occupies critical role.Carbazole also has multiple use in dyestuff and plastics industry.

The production of present domestic anthracene, carbazole, raw material crude anthracene, crude anthracene mainly contain anthracene, carbazole, phenanthrene, and the technology of domestic use is, extracts anthracene earlier with the DMF solvent, and the shortcoming of this technology is that anthracene contains and can only reach 90%.Extract carbazole again from the DMF mother liquor, with the thick carbazole after the DMF solvent recuperation, S-100 solvent wash recrystallization 8～12 times, the content of carbazole can only reach 95%, yield about 30～40%.

The contriver has carried out the research of two more than ten years to the technology of anthracene, carbazole production, and anthracene reaches more than 96%.The content of carbazole reaches more than 98%, and yield reaches more than 80%.

Summary of the invention:

1, removes the maximum phenanthrene of content with S-100 mother liquor washing crude anthracene

Crude anthracene mainly contains anthracene, carbazole, phenanthrene, and the domestic technology of using is to be raw material with crude anthracene, extracts anthracene earlier with the DMF solvent, extracts carbazole again from the DMF mother liquor.The shortcoming of this technology is that anthracene contains and can only reach 90%, and carbazole content is difficult to reach 95%.This technology is to wash crude anthracene with the S-100 mother liquor earlier, uses DMF solvent extraction anthracene again, and anthracene can reach more than 96%, extracts carbazole again from the DMF mother liquor, and carbazole content reaches more than 98%.

2, the evaporation of thick carbazole

This technology has increased the evaporization process of carbazole, and the thick carbazole after the DMF solvent recuperation adds evaporating kettle, and carbazole evaporates under melted state, and evaporant enters trap, enters carbazole recrystallization operation after collecting.The evaporization process of carbazole is to isolate anthracene from the fore portion evaporant, isolates solid substances such as high boiling substance and sand grains in the evaporant of rear section, guarantees that carbazole content reaches more than 98%.

Embodiment

1, removes phenanthrene with S-100 mother liquor washing crude anthracene

Crystallizer adds carbazole primary crystallization operation exhausted S-100 solvent mother liquor, starts and stirs, and adds crude anthracene, and the sealing manhole plate is opened steam valve, and steam is adjusted to 0.3Mpa, and temperature rises to 120 ℃, closes steam valve, is incubated 30 minutes.Cool to 90 ℃, open water coolant, crystallisation by cooling.Temperature is cooled to 30 ℃ in the crystallizer, and the crystallization material is put into and drawn filter pocket, filters and enter the crystallization first time of anthracene.

2, the primary crystallization of anthracene

Crystallizer adds the DMF mother liquor, opens stirring, adds filter also, closes manhole, and chuck feeds the 0.3MPd steam heating, stops to heat to 120 ℃, is incubated 30 minutes.The dissolving temperature in the kettle drops to 90 ℃, opens the chuck cooling water valve, and temperature drops to 40 ℃, and the crystallization material is put into whizzer.The filter of whizzer also enters the secondary crystal of anthracene.

3, the secondary crystal of anthracene

Crystallizer adds the DMF solvent, opens stirring, and the filter of adding secondary washing is also sealed manhole, and open empty valve is opened jacket steam heating valve, vapor pressure 0.3Mpa.Be raised to 100 ℃, stop heating, be incubated 30 minutes.Cool to 90 ℃, open the chuck cooling water valve, material is cooled to 40 ℃, and crystallization suspension is put into whizzer, filters and send the oven dry workshop.Dry by the fire in back anthracene content and reach more than 96%.

4, the evaporation of thick carbazole

Thick carbazole after the DMF solvent recuperation is cooled to enter pulverizer below 60 ℃, pulverizes the particle into Φ＜0.5cm.Send into evaporating kettle with worm conveyor, seal manhole after feeding in raw material, fill up water coolant.Firing up, 240 ℃ start stirring.300-350 ℃ goes out carbazole, and it is not high just to have begun carbazole content, deposits separately, adds the crystallization for the third time of anthracene workshop.Residue carbazole content height enters the carbazole Crystallization Procedure.

5, carbazole primary crystallization operation

Crystallizer adds the S-100 mother liquor, opens manhole, starts to stir, and adds the carbazole evaporant, and the sealing manhole is opened the heating steam valve, adjusts vapor pressure 0.3MPa.Be warmed up to 120 ℃.Stop heating, close the heating steam valve, be incubated 30 minutes.Material cools to 90 ℃, opens water coolant.Temperature is reduced to 30 ℃, opens the discharging valve, and crystallization suspension flows into the suction strainer groove, filters and enter the secondary crystal of carbazole.

6, the secondary crystal of carbazole

Crystallizer adds the S-100 solvent, opens and stirs, and adds carbazole crystalline filter for the first time also, closes manhole, opens the steam heating valve, adjusts vapor pressure 0.3Mpa, and 120 ℃ stop heating, close the steam heating valve, are incubated 30 minutes.The dissolution kettle temperature drops to 90 ℃, opens cooling water valve.The crystallizer temperature is reduced to 40 ℃, closes the cooling water valve of crystallizer, and crystallization suspension is put into whizzer, and filter is oven dry also, obtains content and reaches carbazole more than 98%.

Claims (2)

1. remove the maximum phenanthrene of content with S-100 mother liquor washing crude anthracene

Crude anthracene mainly contains anthracene, carbazole, phenanthrene, and the domestic technology of using is to be raw material with crude anthracene, extracts anthracene earlier with the DMF solvent, extracts carbazole again from the DMF mother liquor.The shortcoming of this technology is that anthracene contains and can only reach 90%, and carbazole content is difficult to reach 95%.This technology is to wash crude anthracene with the S-100 mother liquor earlier, uses DMF solvent extraction anthracene again, and anthracene can reach more than 96%, extracts carbazole again from the DMF mother liquor, and carbazole content reaches more than 98%.

2. the evaporation of thick carbazole

This technology has increased the evaporization process of carbazole, and the thick carbazole after the DMF solvent recuperation adds evaporating kettle, and carbazole evaporates under melted state, and evaporant enters trap, enters carbazole recrystallization operation after collecting.The evaporization process of carbazole is to isolate anthracene from the fore portion evaporant, isolates solid substances such as high boiling substance and sand grains in the evaporant of rear section, guarantees that carbazole content reaches more than 98%.