焦油酸结晶加合法提纯喹哪啶

Purification of Quinaldine Through Additive Crystallization with Tar Acids as Adducts

以焦油酸为结晶加合剂,通过结晶加合法对粗喹哪啶进行提纯,利用GC方法考察了焦油酸种类、原料比及溶剂甲苯用量对产品收率及纯度的影响。实验结果表明,适宜的结晶加合剂为邻甲酚;当第一次结晶不加甲苯,m(粗喹哪啶)∶m(邻甲酚)=1.5∶1时,经三次结晶,喹哪啶的收率为53.6%,纯度为99%(w)。在第一次结晶时加入甲苯可提高产品的收率及纯度,适宜的原料比为:m(粗喹哪啶)∶m(邻甲酚)∶m(甲苯)=7.5∶5∶1,再经重结晶和三次结晶,产品纯度能达到99%(w)以上,总收率可达58.5%左右。重结晶和三次结晶母液可作为结晶溶剂循环利用。

Crude quinaodine was purified by additive crystallization with tar acids. The effects of the tar acid types,raw material ratio and toluene solvent dosage on the yield and purity of the product quinaodine were investigated by means of GC. The results indicated that o-cresol was the optimum crystallization additive. When toluene was not added in the first crystallization and m（crude quinaodine）∶m（o-cresol） was 1.5∶1,the purity and yield of the product quinaldine were 99%（w）and 53.6% respectively after crystallization 3 times. When toluene was used as the solvent in the first crystallization,the purity and yield of the product could be improved. Under the optimum raw material ratio of m（crude quinaodine）∶m（o-cresol）∶m（toluene） 7.5∶5∶1,through recrystallization 3 times,the purity and yield of the product quinaldine reached 99%（w） and 58.5%,respectively. The mother liquid of the recrystallization can be reused as the crystallization solvent.