木质纤维素吸附分离法纯化茶多酚研究

Extracting Tea Polyphenols Using Lignocellulose Adsorbent Followed by Water Elution

选用经过预处理的白杨树、杉木、松树的木屑、铁观音乌龙茶茶梗及大孔树脂、活性炭(颗粒)作为吸附剂,对直接采用鲜叶提制的茶多酚浓缩液进行静态和动态吸附及常温纯净水洗脱试验,以筛选出较好的木质纤维素吸附剂,实验结果表明,杉木木屑是首选的木质纤维素制备原料,选用经过酸碱预处理的杉木木屑作为吸附剂,对茶多酚浓缩液进行动态吸附,进液流速控制在3 mL·min^(-1),总儿茶素的平衡吸附量为107.93 mg·g^(-1);再用常温纯净水进行洗脱,控制流速2 m L·min^(-1),总儿茶素的解吸率为26.21%。

This study attempted to apply lignocellulose to adsorb polyphenols from the extract of fresh tea leaves followed by water-elution to obtain purified and concentrated tea polyphenols. Static and dynamic adsorption using acid-and-alkali pretreated sawdust of poplar, cedarwood, and pine, Tie-guanyin oolong tea stalks, macro-porous resin, and granular activated carbon were conducted. The results indicated that cedarwood sawdust was the preferred raw material for the process. At the tea extract feeding speed of 3 m L·min（-1）, the equilibrium adsorption of catechins was found to be 107.93 mg·g（-1）. Subsequently, washing with purified water on the adsorbent at ambient temperature and a flow rate of 2 m L·min（-1） achieved a catechins desorption rate of 26.21%.