应用化学 ›› 1989, Vol. 0 ›› Issue (2): 95-99.

• 研究简报 • 上一篇    

脂肪酸离子排斥分配色谱分离中的吸附作用

赵国良, 刘志广, 张述忠   

  1. 大连理工大学化学系
  • 收稿日期:1988-04-25 修回日期:1988-08-16 出版日期:1989-04-10 发布日期:1989-04-10

STUDY ON THE ADSORPTION EFFECT IN IONEXCLUSION DISTRIBUTION CHROMATOGRAPHIC SEPARATION OF FATTY ACIDS

Zhao Guoliang, Liu Zhiguang, Zhang Shuzhong   

  1. Department of Chemistry, Dalian University of Technology
  • Received:1988-04-25 Revised:1988-08-16 Published:1989-04-10 Online:1989-04-10

摘要: 酸在氢型阳离子交换树脂柱上的分离机理已有研究,Glod等根据离子排斥色谱中的Donnan膜平衡,推导出分配系数Kd与酸离解常数Ka的关系,能大致预测酸的流出顺序,但不能说明为什么pKa极为相近的有机酸却有较大的保留时间差别.Bafna等从分子吸附的角度考察了某些有机酸在阳离子交换树脂上的吸附平衡和洗脱行为.

关键词: 离子排斥色谱, 脂肪酸, 吸附作用

Abstract: The adsorption effects in ion-exclusion chromatographic separation of formic, acetic,propionic, iso-butyric, butyric, iso-valeric and valeric acids have been studied. It isassumed that both Donnan membrane equilibrium and adsorption equilibrium are involvedin chromatographic process. Thus, the following equation expressing the distribution coef-ficient, Kd, can be derived when water is used as an eluent: Kd=(K+1){[1+4(2+K)C/Ka]1/2-1)/(2K+3+[1+4(2+K)C/K2]1/2)where K, Ka and C are adsorption equilibrium constant, dissociation constant and acid con-centration at peak maximum respectively.The adsorption equilibrium constants of some fatty acids are estimated from the reten-tion data. Linear relationship between lnK and topological parameters, 1x are observed.

Key words: Ion-exclusion chromatography, Aliphatic acids, Adsorption