塔拉粉一步法制备焦性没食子酸的研究

STUDY ON ONE-STEP METHOD FOR PREPARING PYROGALLOL FROM TARA POWDER

以塔拉粉（Ｔａｒａｐｏｗｄｅｒ）为原料，采用一步法制备焦性没食子酸．研究表明，合理的反应条件为：塔拉粉与水的配比为１∶３，氧化钙用量为１５％～２５％，反应温度为２００℃，反应时间为３ｈ．产品用二甲苯提纯，其质量达到试剂标准，焦性没食子酸含量为９９．０％（ＨＰＬＣ法）．每生产１ｔ焦性没食子酸需塔拉粉７．７ｔ（气干）．

Pyrogallol was prepared by one-step method from tara powder.The reasonable conditions of reaction were found as:ratio of tara powder to water:1:3 by weight,quantity of calcium oxide added:15%～25% on tara powder,reaction temperature:200℃ ,and reaction time:3 h.The product,after purified with xylene,met the requirement of reagent standards of pyrogallol.The content of pyrogallol was 99.0%(HPLC method).I t of pyrogallol could be obtained from 7.7 t of tara powder (air dried).