Emulsion crystallization method of preparing crude anthracene from anthracene oil

Abstract

The invention provides an emulsion crystallization method of preparing crude anthracene from anthracene oil, comprises the following steps: heating anthracene oil with anthracene content of 8-10%(wt) to 85-95 DEG C to completely melt, adding a surfactant and water, stirring and uniformly mixing to form emulsion, cooling to 35-40 DEG C, transferring crystal slurry into a centrifuge to centrifuge to obtain the crude anthracene product. The method only needs one crystallization operation, the process flow is simple, the anthracene content of the prepared crude anthracene product is 44-47%(wt), the average grading is 450-600 microns, the process mass yield is 8-11%. By adding less cheap surfactant and water, the anthracene oil with great viscosity can form the emulsion, the crystal substance system viscosity is reduced, the mixing effect is improved, the material is hard to adhere on the wall in the crystallization process, the mass transfer and heat transfer are enhanced, the operation time is shortened, and the purity and the yield of the crude anthracene product are beneficial to improvement.

Description

technical field [0001] The invention belongs to the field of chemical engineering coal tar separation and purification, in particular to an emulsion crystallization method for preparing crude anthracene from anthracene oil. technical background [0002] Anthracene oil is a fraction in the distillation range of 300-360°C from high-temperature distillation of coal tar, in which the anthracene content is between 7% and 10%. Anthracene oil is purified by crystallization to obtain crude anthracene, which contains 10-20 compounds, most of which are polycyclic aromatic compounds. The main components of crude anthracene are: anthracene 35%-45%, phenanthrene 15%-25% , carbazole 10% to 20%. Crude anthracene is further purified to obtain higher purity anthracene, phenanthrene and carbazole. These three substances are important chemical raw materials and are widely used in medicine, dyestuffs, pesticides and other industries. Anthracene with a purity greater than 99.99% can be used to ...

AI Technical Summary

Problems solved by technology

Since anthracene oil contains a large amount of high-melting point substances and has a high viscosity, there are the following main problems in the production of crude anthracene crystallization: (1) The particle size of crude anthracene is small, with an average particle size of about 200 μm, serious inclusions in the product, low anthracene content, and difficult It can reach more than 40%; (2) Due to the high viscosity of the material system, during the cooling and crystallization process, the crystals are easy to adhere to the wall of the vessel, increasing the heat transfer resistance and affecting the production capacity of the crystallization device; (3) The crystal slurry is highly viscous and centrifuged difficulty

The production process of crude anthracene crystallization has the problems of high crystal slurry viscosity and small particle size of crude anthracene, which is difficult to centrifuge. The modification of the crystallizer agitator or centrifugal separation equipment has not fundamentally solved the problem of small crude anthracene particle size and difficult centrifugation