从乙二胺副产的多乙烯多胺混合物中分离哌嗪

SEPARATING PIPERAZINE FROM ETHYLENEDIAMINE BYPRODUCT POLYETHYLENE POLYAMINES MIXTURE

通过冷冻、共沸蒸馏 ,从多乙烯多胺混合物中分离出哌嗪。分离工艺的较优化条件为 :原料经 -5～ 0℃冷冻 4 8h后真空抽滤出液体 ,与石油醚共沸蒸馏 ,经单纯搜索法确定回流比为 4∶ 1 ,m (共沸剂 )∶m(滤饼 ) =1 .3∶ 1 ,所得哌嗪纯度为 98.5% ,质量符合美国药典规定 ,收率 85%。

Piperazine was separated from ethylenediamine byproduct polyethylene polyamines mixture by refrigeration and azeotrope distillation. The influences of the temperature and azeotrope agent on the yield were studied by simple search method. The optimum conditions found for separating piperazine were refrigerating at -5～0 ℃ for 48 h and m(azeotropic agent petroleum benzine)∶ m(fiter cake)= 1.3∶1, the reflux ratio=4∶1. The purity of piperazine was 98.5% and the yield was 85%.