007×7强酸型阳离子树脂静态吸附K^+的特性

Characteristics research on adsorption K^+ with 001×7 resin

为了探索离子交换法吸附回收工业废液中的K+,通过001×7强酸型阳离子树脂吸附KCl溶液中K+的实验,考察了不同KCl溶液浓度、操作温度和树脂粒径下K+的静态吸附特性,并用动边界模型描述树脂吸附K+的过程,确定了吸附过程的速度控制步骤,建立了吸附过程的动力学总方程.结果表明,001×7强酸型阳离子树脂吸附K+的过程为颗粒扩散控制;随着吸附时间增加,静态吸附过程呈现快速吸附阶段、缓慢吸附阶段和吸附平衡阶段的3阶段变化特征;溶液初始K+浓度越大,初始阶段吸附速率越大,达到平衡时溶液的浓度越大、单位树脂吸附量越大、溶液吸附率越低;操作温度升高和树脂粒径减小,均有利于吸附过程进行.

In order to explore the method of ion exchange adsorbing K＋ in industrial waste liquid, the experiment of 001 × 7 strong acid cation exchange resin adsorption in K＋ in KCl solution was used to investigate the influences of different concentration of KCl, temperature and particle size of resin on the static adsorption characteristics of K＋. Moving boundary model was applied to describe the adsorption ofK＋ on the resin, determine the control step ofadsorption process, andestablish the dynamic equation of adsorption process. The results show that the dominant procedure of 001 × 7 strong acid type cation exchange resin adsorping K＋ is intraparticle diffusion. With the increase of adsorption time, the static adsorption process present various characteristics in three stages as rapid absorption stage, slow adsorption stage and adsorption equi- librium stage. The greater the initial concentration of K＋ in the solution, the larger the adsorption rate of initial stage is; the greater the concentration of the solution at equilibrium and the average adsorbance of resin is, the lower the adsorption efficiency of the solution is. Raising the temperature and reducing the resin particle size are conducive to the adsorption process.