基于乙酰苯胺重结晶实验的热过滤环节教学改进

Reform of hot filtration teaching based on acetanilide recrystallization experiment

近年来,我校药学专业、中药学专业、药物制剂专业所用的“有机化学”教材中重结晶实验操作的热过滤环节采用的是经典的保温漏斗过滤法,发现学生在实际操作过程中总会造成大量晶体损失。为此,在实验课堂上对热过滤环节进行了大胆的改进尝试:用抽滤的方法代替利用保温漏斗进行的热过滤,即将配制好的乙酰苯胺热饱和溶液倒入事先准备好的瓷质布氏漏斗中,进行抽滤,快速地将活性炭及杂质与母液分离。经改进之后,乙酰苯胺的重结晶实验产率由之前的42%左右增加到90%左右,大大降低了实验消耗。

In recent years,in the“Organic Chemistry”textbook used in the pharmacy,Chinese pharmacy,and pharmaceutical preparation specialties of our school,the classical heat preservation funnel is still used in the hot filtration process of recrystallization experiments,and it is found that students will always cause problems in the actual operation process.A lot of crystal loss phenomenon.To this end,we have boldly tried to improve the hot filtration process in the experimental classroom:instead of using hot-filters for hot filtration,use a suction filtration method,and pour the prepared hot saturated acetanilide solution into the prepared porcelain.In the Buchner funnel,suction filtration is performed to rapidly separate activated carbon and impurities from the mother liquor.After the improvement,the recrystallization rate of acetanilide was increased from about 42%to about 90%,greatly reduces the experimental consume.