分子筛固定床脱水合成乙酰苯胺

STUDU ON SYNTHESIS OF ACETANILIDE BY DEHYDRATION ON ZEOLITE IN A FIXED BED

为克服乙酰苯胺传统生产工艺的不足,采用苯胺为原料、冰醋酸为酰化试剂、分子筛固定床脱水,回流反应合成乙酰苯胺。考察了分子筛、锌粉用量、n(冰醋酸)/n(苯胺)、回流时间对实验结果的影响,较佳的工艺条件为:分子筛用量为30%、n(冰醋酸)/n(苯胺)为3、锌粉用量为2.8%、回流反应2 h;在此条件下,分子筛固定床连续循环使用,产物收率大于96.0%、纯度达99.6%。

In order to overcome the shortcomings of traditional production process of acetanilide,acetanilide was synthesized by using aniline as raw material,glacial acetic acid as acylation reagent,molecular sieve in a fixed bed as a dehydration catalyst under reflux conditions.The effects of molecular sieve,zinc powder,nglacial acetic acid/naniline and reflux time on the experimental results were investigated.The optimum reaction conditions were as follows:30%molecular sieve;n(glacial acetic acid)/n(aniline)is 3∶1;2.8%zinc powder,and refluxing for 2 h.Under these optimized conditions,the yield and purity of the product could reach 96.0%and 99.6%,respectively.