Box-Behnken设计-效应面法优化离子液体提取废次茶叶中咖啡因工艺

Optimization of Ionic Liquids Extraction of Caffeine from the Discarding Tea by Box-Behnken Design and Response Surface Analysis

以咖啡因的提取率为评价指标,在单因素实验基础上,通过Box-Behnken设计-效应面法考察料液比、浸提时间、浸提温度、离子液体[HSO_3-pmim]^+[HSO_4]^-浓度4个因素对咖啡因提取率的影响。实验结果表明,离子液体[HSO_3-pmim]^+[HSO_4]^-提取咖啡因的最优提取工艺为:料液比为0.05 g/mL,浸提时间为160 min,浸提温度为90℃,离子液体浓度为70%,咖啡因的提取率为95.1 mg/5 g茶样。Box-Behnken设计-效应面法优化离子液体[HSO_3-pmim]^+[HSO_4]^-提取废次茶叶中咖啡因,提取工艺合理,方法简便,精确度高,可预测性好。

With extraction yield of caffeine as evaluation index, the effects of liquid-solid ratio, extraction temperature, extraction time, concentration of ionic liquids [ HSO3-pmim] · [ HSO4 ] - were investigated through Box-Behnken design and response surface methodology based on single factor experiment. The results suggested that the optimal conditions of extraction technology were as follows：liquid-solid ratio was 0.05 g/mL, extraction time was 160 rain, extraction tempera- ture was 90 ℃, ionic liquids [ HSO3-pmim ] · [ HSO4 ] ＂concentration was 70%. Under these conditions the extraction yield of caffeine was 95.1 mg/5g tea sample. The optimized extraction technology was reasonable, simple, precise and with good predictability.