乙烯焦油中萘系芳烃的预富集技术研究

Study on the preconcentration technology of naphthalene aromatics in ethylene tar

关键词:  乙烯焦油  萘  甲基萘  预富集

Key words:  ethylene tar  naphthalene  methylnaphthalene  preconcentration

摘要:

通过分析乙烯裂解装置所副产乙烯焦油的基本性质和组成,开发出一种新的乙烯焦油中萘系芳烃的预富集技术。筛选、复配一种高选择性复合萃取剂R,在温和条件下实现对乙烯焦油原料中高附加值双环萘系芳烃组分(萘、α-甲基萘、β-甲基萘)的高效预富集。最佳萃取条件下抽出油收率为55.46%,萘、β-甲基萘、α-甲基萘的萃取回收率分别为96%、93%、91%。与乙烯焦油原料直接精馏切割相比,抽出油后续采用精馏切割工艺,原料处理量大幅减少。且萃取后脱除了易聚合、结垢的活性组分,设备不易因结垢而堵塞,装置运行周期延长。另外,萃取使得油料轻质化,精馏操作单元苛刻度减小,且后期精馏时各组分分离难度降低,产品质量提高。 

Abstract:

Based on deep research of the basic properties and compositions of the by-product ethylene tar from ethylene cracking unit, a new highly efficient preconcentration technology of naphthalene aromatics in ethylene tar was developed. A high selective extractant R was prepared to achieve high-efficiency preconcentration of high value-added biocyclic naphthalene aromatic components (such as naphthalene, α-methylnaphthalene, β-methylnaphthalene) under mild conditions. Under the optimum extraction conditions, the yield of extracted oil is 55.46%, the extraction recovery of naphthalene, β-methylnaphthalene and α-methylnaphthalene is 96%, 93% and 91%, respectively. Compared with the direct distillation of ethylene tar, handling capacity of raw material for subsequent distillation cutting process is reduced substantially. The active components which are easy to polymerize and scale can be removed by extraction.Accordingly, the equipment is not easy to be blocked due to scaling, and the operation cycle is prolonged. Moreover, the extraction process makes the oil more lighter, reduces the severity of the distillation unit and the separation difficulty of each component in the later distillation, and improves the product quality.