含萘量较低煤焦油中萘的分离与提纯 -

报道了一种从含萘量较低的煤焦油中分离、提纯萘的有效方法。先用乙醇对煤焦油进行萃取,然后对萃出液减压蒸馏,得到含萘量较高的固液混合物,经过滤抽干得到粗萘。建立了水蒸汽蒸馏提纯粗萘的方法,所得的精萘经气相色谱检测其纯度可达99·48%,回收率在93%以上。随后与精馏法、溶剂结晶法等提纯方法进行了比较,体现了水蒸汽蒸馏提纯萘的优越性。 The method of separation and purification of naphthalene from coal-tar oil is described in this paper. There were lower concentrations of naphthalene in the coal-tar oil. Firstly,naphthalene was extracted from coal-tar oil with ethanol. The extract was distilled under vacuum,and the liquid-solid mixture of cut fraction was filtered. The solid compound namely,raw naphthalene was obtained. Distillation with water was investigated in purification of raw naphthalene. The purity of product was 99.28% analyzed by gas chromatography,and the recovery was above 93%. Compared to replicate crystallization and rectification,distillation with water was validated to be an effective method for purification of naphthalene