离子交换树脂吸附TP5的热力学和动力学研究

Kinetics and thermodynamics for ion exchange of TP5 on NH1-resin

针对凝胶型阳离子交换树脂对TP5的吸附行为，研究了间歇反应中TP5水溶液的吸附热力学与动力学特性。热力学研究表明，TP5在所用树脂上的吸附平衡数据符合Langmuir吸附等温方程。在283．15～303．15K之间，TP5的质量浓度在10g／L时，离子交换树脂对TP5的吸附过程可分两个阶段，第一阶段受液膜扩散控制，第二阶段主要吸附过程受颗粒扩散的控制。利用TP5在不同条件下的动态吸附性能实验，考察了pH值、温度、溶液初始浓度、搅拌转速等因素的影响。采用两相阻力模型描述了TP5在离子交换介质中的动态吸附性能，通过计算得到了TP5在吸附剂颗粒中的颗粒扩散系数，有助于进一步研究小肽在吸附过程中的传质现象。

The adsorption kinetics and thermodynamics of TP5 in solution was studied. Thermodynamic studies indicate that TP5 adsorption onto NH1 resin conforms to Langmuir model. At the 10 g/L concentration of TP5 and the temperature from 283.15 K to 303.15K, the adsorption process could be divided into two phases. The film diffusion gives priority to the adsorption at the initial period, and the adsorption fits well into pore diffusion limitation at the following period which predominates the ion exchange adsorption. Several factors such as pH, temperature, initial concentration of TP5 and the stirring speed were investigated by batch experiments. The two-phase resistance model properly describes the kinetics of TP5 adsorption onto ion-exchange resin. Using this model and the adsorption data, the particle diffusion coefficients were determined, which can be used in further research work on ion exchange of small mass peptides.