吲哚的结晶提纯研究

Crystallization purification of indole

以煤焦油中提取的粗吲哚为原料,通过工业常用的结晶提纯技术进行分离精制,考察了不同的溶剂类型、结晶溶剂质量比、溶剂中关键溶剂与惰性溶剂质量比、结晶温度及原料中吲哚质量分数等因素对吲哚结晶产品收率和产品纯度的影响。结果表明:较适宜的溶剂类型为甲醇水混合溶剂,溶剂质量比为1.5,混合溶剂中甲醇与水的质量比为3∶2,结晶温度为0℃,适宜应用结晶进行分离的原料吲哚质量分数应不低于80%,90%以上最佳,在此条件下进行结晶可以获得白色片状吲哚晶体,产品纯度高于99%,产品收率在75%以上。

With the crude indole extracted from coal tar as raw material,the purification of indole is carried out through crystallization,a basic industrial purification technology.The effects of types of solvent,ratio of the key solvent and the inert solvent,solvent ratio,crystallization temperature and the indole content in raw materials on the yield are studied.The optimal crystallization conditions are shown as follows：mixed methanol and water as suitable solvent,3：2 of methanol and water in mixed solvent,0℃ of crystallization temperature,more than 80％ （better above 90％） of indole content in the raw material.Under such conditions the purity and yield of indole is over 99％ and higher than 75％,respectively.