茶多酚在水和N,N-二甲基甲酰胺中的溶解行为及动力学模型

用电导方法研究了茶多酚在水和二甲基甲酰胺(DMF)溶剂中的溶解行为,并导出了溶解动力学模型:dC/dt=k2C2+k1C+k0。结果显示,茶多酚溶液的浓度、溶解温度以及溶剂都会影响其溶解行为。温度升高,有利于茶多酚的溶解;增大茶多酚在溶液中的浓度,反应速率加快,而且茶多酚在H2O中比在DMF中更容易溶解,这跟溶剂本身的酸碱性有关。通过建立溶解动力学模型发现,所有的溶解过程基本上都是零级反应,其次是一级反应,而基本上不发生二级反应。

Dissolution of Tea Polyphenol in Water and DMF and Related Dynamic Model

Applying conductivity as a measure,dynamic behavior for dissolution of tea polyphenols in two solvents,e.g.water and N,N-dimethyl formamide(DMF),respectively,as investigated and a mathematical model was further deduced as: dC/dt = k2C2 k1C k0.The results indicated that solvent,concentration and temperature are important factors for dissolution of tea polyphenols.For example,the increase of the temperature,the rate for dissolution of tea polyphenols would be visibly increased,while this behavior is also observed for increasing the concentration of the tea polyphenols solution.A comparison of the effect from two solvents indicated that the tea polyphenols is easily dissolved in water and the possible reason is due to these two solvents with different acid-base properties.The model suggested that the dissolution of tea polyphenols in these two solvents follows the zero order reaction basically.