加酸内部沸腾法提取氯化两面针碱及其纯化研究

Study on Extraction and Purification of Nitidine Chloride by Acid Inner Ebullition

为降低两面针生物碱提取过程酸对设备的腐蚀及提高纯化过程的回收率,采用了加酸内部沸腾法强化提取氯化两面针碱,提取液直接用阳离子交换树脂吸附及超声波辅助强化洗脱在树脂表面结晶出来的两面针生物碱晶体。实验结果表明:两面针粉末先用4倍物料量的乙醇盐酸解吸剂解吸,解吸剂中盐酸和乙醇的质量浓度分别为0.61%和80%,然后用16倍物料量的20%质量浓度的乙醇在82℃下提取4 min,在此条件下氯化两面针碱提取得率为0.134%;用732阳离子交换树脂直接在40℃下静态吸附133倍树脂用量的内部沸腾法提取液,用盐酸浓度为3 mol·L-1、乙醇质量浓度为70%的酸乙醇洗脱液在超声波的辅助下间歇解吸附,解吸率达到99%以上,分离得到的氯化两面针碱纯度为94.5%,回收率为77.7%。与传统酸醇回流提取对比,加酸内部沸腾法提取快37.5倍、乙醇和盐酸消耗量减少一倍,对设备腐蚀大为减轻,提取液可以用阳离子交换树脂直接富集分离,氯化两面针碱回收率提高24.2%。

In order to reduce equipment corrosion during typical zanthoxylum nitidum alkaloid extraction processes and improve nitidine chloride yield during purification processes, an acid inner ebullition method was used to intensify the extraction of nitidine chloride. The zanthoxylum nitidum alkaloid in the extraction solution is directly adsorbed by cationic exchange resins, and then desorbed under ultrasonication. The experimental results show that when the zanthoxylum nitidum powder is immersed into 4 mL.g^-1 solvent （which was composed of 80%（wt） ethanol and 0.61%（wt） HC1）, and then extracted by 16 mL.g^-1 of another solvent （which was composed of 20%（wt） ethanol） at 82℃ for 4 min, the yield of nitidine chloride is 0.134%. The extraction solution is treated with cationic exchange resin 732 at 40℃ （the ratio between the extraction solution and the resin is 133：1） and the adsorbed zanthoxylum nitidum alkaloid was desorbed in acid ethanol under ultrasonication. The desorption ratio, nitidine chloride yield and the purity of nitidine chloride are 99%, 77.7% and 94.5%, respectively. Compared with the acid ethanol refluxing extraction, the acid inner ebullition possesses much higher reaction rate （up to 37.5 times） and also consumes less ethanol and chloride acid （up to 50%）, which reduces equipment corrosion. In addition, the extraction solution was directly purified by the cationic exchange resin and the nitidine chloride yield is improved by 24.2%.