Abstract: Through comparing adsorption and desorption characteristics of milk vetch root (Astragalus) isoflavones on five types of macroporous resin, it was found that X-5 macroporous resin was the most suitable one for the adsorption of isoflavones. Static adsorption experiments were carried out to investigate the adsorption kinetics and thermodynamics. Kinetics study indicated that the adsorption process could be best described by the pseudo-second-order model, and was controlled mainly by intra-particle diffusion. The isothermal adsorption followed the Langmuir model. The thermodynamic properties, i.e. ΔG0<0, ΔH0=8.021 kJ/mol and ΔS0=62.51J/(mol?K), revealed that the adsorption process was spontaneous, endothermic and feasible and the change in enthalpy was the main driving force for the adsorption of isoflavones on X-5 macroporous resin.

Key words: X-5 macroporous resin, isoflavones, kinetics, thermodynamics

摘要： 通过对比5种大孔树脂对黄芪异黄酮的吸附和解吸特性，发现X-5大孔树脂最适用于吸附黄芪异黄酮，并进一步采用静态吸附法研究了X-5树脂对黄芪异黄酮的吸附动力学和热力学特性。动力学研究表明,准二级动力学相对于其它模型而言能够更好地描述黄芪异黄酮的吸附过程，颗粒内扩散是整个吸附过程的主要速率控制步骤；黄芪异黄酮的吸附符合Langmuir等温吸附模型。热力学研究表明，ΔG0<0即吸附是自发进行的，ΔH0和ΔS0分别为8.021 kJ/mol和62.51 J/(mol?K)说明X-5大孔树脂对黄芪异黄酮的吸附是以熵为主要驱动力的吸热 过程。

关键词: X-5大孔树脂, 黄芪异黄酮, 动力学, 热力学