碳基固体酸催化合成乙酰水杨酸

Synthesis of acetylsalicylic acid catalyzed by carbon-based solid acid

以淀粉和对甲苯磺酸为原料合成了碳基固体酸催化剂,并采用FTIR、TG、BET、SEM和EDS对催化剂进行了表征。研究了催化剂对乙酰水杨酸合成反应的催化活性,并比较了常规加热和微波加热方式对反应的影响。通过单因素试验确定了较佳工艺条件为:乙酸酐与水杨酸物质的量比为1.5∶1,催化剂用量为水杨酸质量的5.8%,反应时间25 min,反应温度76～80℃。常规加热条件下收率82.1%,使用5次后,收率仍保持在78.2%。碳基固体酸催化剂在常规加热条件下催化性能和重复使用性能均优于微波加热条件反应。

Carbon-based solid acid catalysts synthesized from starch andp-toluene sulphonic acid were characterized by FTIR, TG, BET, SEM and EDS. Its catalytic activity and effect of conventional heat and microwave heat on yield of acetylsalicylic acid were studied. The better condition was determined with single factor tests, which is as follows： the molar ratio of acetic anhydride to salicylic acid was 1.5 ： 1, the weight ratio of carbon-based solid acid to salicylic acid was 5.8%, acylation reaction temperature was 76--80 ~C, reaction time was 25 min under conventional heat. The yield of acetylsalicylic acid was 82.1% and kept 78.2% after used five times under conventional heat. The carbon-based solid acid catalyst has high catalytic activity and retrievability under conventional heat, which are better than that of microwave heat.