Acta Chimica Sinica ›› 1995, Vol. 53 ›› Issue (4): 369-375. Previous Articles     Next Articles

Original Articles

反相高效液相色谱中溶质保留过程的热力学研究Ⅰ: 柱相比, 吉氏自由能变及其分量, 吸附和解吸附自由能变

耿信笃   

  1. 西北大学现代分离科学研究所
  • 出版日期:1995-04-15 发布日期:1995-04-15

Studies on thermodynamics in solute retention of reversed-phase high performance liquid chromatographyⅠ: Column phase ratio, gibbs free energy change and its fractions, adsorption and desorption free energy changes

GENG XINDU   

  • Online:1995-04-15 Published:1995-04-15

Based on thermodynamical standpoint, a new definition of column phase ratio in reversed-phase high performance liquid chromatography (RP-HPLC) and its determination method are presented. The contribution of the column phase ratio defined in this paper was found to be comparable to the Gibbs free energy change of solute during stoichiometric displacement process. The Gibbs free energy change of solute △G~(Pα) during chromatogrpahic process may be divided into two independent fractions expressing adsorption and desorption free energy changes △G~(Ⅰ,α) and △G~(Z,D), due to the stoichiometric displacement model for retention of solute. Both △G~(Ⅰ,α) and △G~(Z,D) under different compositions of mobile phase may be evaluated with equations derived in this paper. Compared to the experimental results, the relative deviation of the expected one's is generally lower than ±2%.

Key words: ADSORPTION, THERMODYNAMICS, REVERSED PHASE CHROMATOGRAPHY, DESORPTION, GIBBS FREE ENERGY

CLC Number: