聚酰胺树脂对茶多酚和咖啡因吸附选择性研究

本文用紫外可见分光光度法研究了聚酰胺树脂对茶多酚和咖啡因的吸附性能 ,分光光度法和HPLC研究表明 ,聚酰胺树脂对茶多酚的吸附能力远大于对咖啡因的吸附能力 ,氢键起了非常重要的作用。在2 0g聚酰胺树脂对 1 0 0mL 0 71g·L- 1 咖啡因水溶液的静态吸附实验中 ,其吸附量为 2 65mg·g- 1 ,吸附率为7 5 % ;8 0g聚酰胺树脂对 70 0mL 1 98g·L- 1 茶多酚水溶液的静态吸附实验 ,吸附量高达 1 4 8 1 3mg·g- 1 ,吸附率为 85 5 % ;以 85 %的乙醇为洗脱剂 ,咖啡因和茶多酚的解吸率分别为 74%和 90 % ;同时聚酰胺树脂对咖啡因和茶多酚的静态吸附在 80min内达到快速吸附平衡 ,并且吸附动力学曲线接近线性。利用树脂成功地将茶多酚和咖啡因混合溶液进行了吸附分离 ,得到的产品茶多酚含量高于 96 % ,其中EGCG含量高于80 % ,而咖啡因含量则小于 2 82 %。实验结果表明 ,聚酰胺树脂适合吸附分离咖啡因和茶多酚。

Study on Adsorption of Tea Polyphenol and Caffine with Polyamide Resin

The performance of adsorption of tea polyphenol and caffine with polyamide resin was investigated. The results obtained by spectrophotometry and HPLC show that the ability of adsorption of tea polyphenol with polyamide is stronger than that of caffine, in which hydrogen bond plays a very important role. The adsorption amount of caffine is 2.65 mg.g-1 with 7.5% adsorption ratio when 100 mL of 0.71 g.L-1 caffine is adsorbed on polyamide resine, but the adsorption amount of tea polyphenol is up to 148.13 mg.g-1 with 85% adsorption ratio when 700 mL of 1.98 g.L-1 tea polyphenol is adsorbed on polyamide resine. The dilution ratios of caffine and tea polyphenol are 74% and 90%, respectively, when they are diluted by 85% alcohol. The static adsorptions of caffine and tea polyphenol on polyamide resine reach equilibrium quickly in 80 min, and the plots of adsorption kinetics are nearly linear. Tea polyphenol and caffine are successfully separated on polyamide resine, and the obtained product contains more than 96% of tea polyphenol and 80% of EGCC with caffine less than 2.8%.