大孔树脂吸附分离黑胡萝卜红色素的研究

Study on Adsorption and Separation of Red Color from Daucus carota L. by Macroporous Resins

采用酸性水溶液浸提法提取黑胡萝卜红色素。用6种大孔树脂(LS-610B、BM3、D101、LSA-40、AB-8、LSA-305)对粗提液进行初步分离纯化,预选出两种(LS-610B、BM3)吸附性能较好的树脂,进行了黑胡萝卜红色素的吸附等温线和静态吸附/解吸动力学实验研究。研究结果表明,树脂吸附的最适宜的料液pH值为2.0;LS-610B树脂适合Langmuir模型和Freundlich模型拟合,相关系数分别为0.979 9和0.974 0;BM3树脂更适合Langmuir模型拟合,相关系数为0.966 2,属于单分子层吸附机理;这两种树脂的吸附过程特征都能用拟一阶动力学模型能很好地描述,主要因素是内外膜扩散影响吸附的;最佳解吸条件为65%乙醇水溶液(含0.3%的柠檬酸)。

Acidic aqueous solution was used as the extractant for the extraction of red color from black carrot.Adsorption of black carrot red color onto six macroporous resins(LS-610 B,BM3,D101,LSA-40,AB-8,LSA-305)was screened to develop a potential approach for large-scale production of black carrot red color,and two promising resins(LS-610 B,BM3)were selected for the following static and dynamic adsorption/desorption experiments. Results showed that the optimal adsorption pH of the extracted solution was 2.0,the adsorption data of resin LS-610 B could be well fitted both by Langmuir and Freundlich equations,with correlated coefficient of0.979 9 and 0.974 0,respectively. The adsorption data of resin BM3 could be better fitted by Langmuir equation,with correlated coefficient of 0.966 2,exhibiting mono-layer adsorption mechanism,and them pseudo first-order model could describe the dynamic model better for the two resins,internal and external diffusion controlling the adsorption rate. The optimal desorption condition was 65 % ethanol aqueous solution containing0.3 % citric acid.