Technological process for preparing durene with reformed C10 aromatic

Abstract

The invention relates to a technique for reforming a C10 arene to produce a durene, the reforming to the C10 arene undergoes steps of continuous rectification, freezing crystallization and separation by three rectification towers for separating out the durene front low-boiling fraction, rectifying out the durene liquid rich mother liquor and then extracting out the product before 205 DEG C by rectification; and the durene rich mother liquor is cooled to the temperature of between -5 and -10 DEG C through a refrigerating kettle, the durene in the rich liquid is saturated and separated out of a crystalline solid, and a solid durene product is obtained through fractional crystallization and pressure filtration. The product of the invention has the yield reaching 80 percent and the purity reaching 99 percent; and the technique is environment-friendly and energy-saving and will not produce smoke gas by applying the coal gas produced by itself. The technique has advantages of reducing the amount of freezing materials, increasing the freezing temperature and obviously saving the power, and has broad application prospect.

Description

technical field [0001] The invention relates to a method for extracting durene from aromatic hydrocarbons, in particular to a process for producing durene by reforming carbon ten aromatic hydrocarbons, specifically a process for producing durene by three-tower continuous rectification, freezing crystallization and separation. Background technique [0002] Durene (1,2,4,5-tetramethylbenzene) is an important organic chemical raw material. It is mainly used in China to produce pyromellitic dianhydride (referred to as homoanhydride or PMDA). PMDA is a synthetic polymer An important raw material for imide polymers. The production of durene in my country is still in the development stage, the main technologies are: C 10 Heavy aromatics crystallization separation method, trimethylbenzene methanol alkylation method, trimethylbenzene chloromethylation method, trimethylbenzene gas phase isomerization disproportionation method, etc. The heavy aromatics crystallization and separation ...

AI Technical Summary

Problems solved by technology

Second, the freezing temperature required in the production of durene is low, for example, to reach -35°C, and the energy consumption is very high

Third, the purity of the product is low, generally 93-

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