烃化法分离间/对甲酚的研究

Study on the separation of meta-and para-cresol with alkyl product

甲酚是邻、间、对甲酚同分异构体的混合物,其中间甲酚是很重要的化工原料,但间甲酚由于直接合成困难,因此只能采取分离的方法获取。由于间/对甲酚的沸点相差很小,通过精馏很难分离,但通过烃化法可使两者沸点差增大,再经精馏得到间/对甲酚烃化物。研究了对甲酚的烃化产物(间/对甲酚烃化物)进行分离,首先通过精馏得到纯度为98.25%的4,6-二叔丁基间甲酚,因烃化反应可逆,4,6-二叔丁基间甲酚可在浓硫酸和较高温度下发生脱烃反应,最终得到纯度为99%的间甲酚,实现间/对甲酚的分离。

Cresol is a isomer mixture that include o-cresol, m-cresol and p-cresol, m-Cresol is the very important industrial chemical. Direct synthesizing m-cresol is hard, m-cresol was obtained by the method of separation. The boiling point of m-cresol and p-cresol is close, it is hard to separate them with fractional distillation. The boiling point of alkyl product of m-cresol and p-cresol is very different, so alkyl product of m-cresol and p-cresol can be prepared with fractional distillation. The product of alkylation of cresol （ m-and p-cresol hydrocarbon compounds） were isolated, purity of 4,6-ditetrabutyl-m-cresol can be up to 98.25% through fractional distillation ,and get 4,6-ditetrabutyl-m-cresol with concentrated sulfuric acid and high temperature. Finally using dealkylation and fractional distillation to get purity of 99% m-cresol.