脱芳复合萃取剂的研究进展

Research development of composite extractants in removal of aromatics

复合萃取剂包括传统复合溶剂和新型复合溶剂。前者是有机溶剂与有机溶剂或无机盐的复配,后者则是不同种类的离子液体复配,它们不仅具有对芳烃的溶解性好、选择性高的优点,而且萃取后,萃余油的收率相对较高,已经成为继单一萃取剂用于油品(石脑油、重整汽油和模拟油等)脱芳烃研究之后又一新的研究热点。本文综述了国内外脱芳烃复合萃取剂的研究进展,重点介绍了两类复合萃取剂(萃取剂与醇类、胺类溶剂或无机盐复配和离子液体复配)在油品萃取脱芳烃中的应用;根据复合萃取剂中助萃取剂的种类不同,对用于萃取脱芳烃的复合萃取剂进行了分类总结;介绍了不同种类的萃取剂复配与不同种类的离子液体复配的研究进展;最后指出复合萃取剂在分离芳烃应用中具有选择性高、分配系数高、操作工艺简单有效且成本低廉等优点,是工业上萃取脱芳烃今后的发展趋势。

The composite extractants include the traditional and the novel composite solvents. The former is the combination of two different organic solvents, or organic solvents and inorganic salts;the latter is the combination of different kinds of ionic liquids, which not only have excellent solubility and selectivity to aromatics, but also have relatively high yield of residual oil after extraction. The ionic liquids have become a new research hotspot after the single extractant used for the dearomatization of oil products(naphtha, reformed gasoline and simulated oil). In this paper, the research progress of composite extractants for aromatics removal around the world was reviewed, and the application of two kinds of composite extractants(extractants mixed with alcohols, amines or inorganic salts and ionic liquids) in the extraction of aromatics from oils was mainly introduced. According to the different kinds of auxiliaries in composite extractants, the composite extractants used for extraction of aromatics were classified and summarized. The research development of different kinds of extractants and ionic liquids was also introduced. Finally, the application of composite extractants in the separation of aromatics which has the advantages of high selectivity, high distribution coefficient, simple and effective operation process and low cost, is the development trend of industrial extraction for aromatics removal in the future are pointed.