正交试验优化活性炭吸附-乙醇重结晶法精制甘草酸单铵盐

Orthogonal Array Design for the Optimization of Monoammonium Glycyrrhizinate Purification by Activated Carbon Adsorption-Ethanol Recrystallization

以含量66.72%、白度31.7的甘草酸单铵盐粗粉为原料,采用乙醇结晶、活性炭脱色、乙醇再次结晶的方法精制甘草酸单铵盐。通过单因素试验考察甘草酸单铵盐与活性炭物料比、脱色时间、脱色温度对甘草酸单铵盐脱色效果的影响,然后采用正交试验的方法,确定脱色的最佳工艺条件。结果表明:最佳工艺条件为:甘草酸单铵盐与活性炭物料比1:3、脱色温度75℃、脱色时间60min。通过重复实验验证,该工艺脱色效果好,工艺稳定,最终获得含量83.32%、白度74.2的甘草酸单铵盐,甘草酸单铵盐收率可达68.74%。

Crude powder containing 66.72% monoammonium glycyrrhizinate（MAG） and having a whiteness of 74.2 was purified using a procedure involving ethanol crystallization followed by activated carbon decolorization and ethanol recrystallization to obtain a purity of 83.32% and a whiteness of 74.2.The effects of monoammonium glycyrrhizinate-to-activated carbon ratio as well as adsorption time and temperature on decolorization efficiency were investigated by one-factor-at-a-time method,and the optimum decolorization conditions were determined using orthogonal array design to be adsorption at 75 ℃ for 60 min with a monoammonium glycyrrhizinate-to-activated carbon ratio of 1：3.Repeated experiments under these conditions indicated that the procedure was stable and effective at decolorizing monoammonium glycyrrhizinate with a recovery of 68.74%.