摘要 |
<p>Disclosed is a process for preparing 5-aminosalicylic acid by gas phase catalytic carboxylation, characterized in that carbon dioxide is introduced into a system of p-acetaminophenol and a basic compound at a temperature of 150°C - 220°C and a pressure of 0.5 - 5.0 Mpa in the presence of a catalyst, so as to carry out a gas phase catalytic carboxylation reaction to form a 5-aminosalicylate, and the crude product 5-aminosalicylate is separated, and then acidified to prepare 5-aminosalicylic acid (5-ASA). Since the gas phase catalytic reaction replaces a solid phase thermo-chemical reaction, the reaction is significantly improved in terms of the process flow, reaction conditions, product quality and energy consumption. In addition, the reaction has a short reaction time, good selectivity, high yield and no formation of wastes during the reaction, and is suitable for industrial production.</p> |
申请人 |
ZHEJIANG HUAHAI PHARMACEUTICAL CO., LTD;LI, GUANGXING;LI, JINJIN;ZHU, DAJIAN;JIANG, QIANG;CAI, LINGLI;XIE, YONG;GAN, LIXIN |
发明人 |
LI, GUANGXING;LI, JINJIN;ZHU, DAJIAN;JIANG, QIANG;CAI, LINGLI;XIE, YONG;GAN, LIXIN |