Acta Phys. -Chim. Sin. ›› 1993, Vol. 9 ›› Issue (04): 516-522.doi: 10.3866/PKU.WHXB19930417

• ARTICLE • Previous Articles     Next Articles

Intrinsic Protonation Constants of Chelating ion Exchange Resin

Tao Zu-Yi; Dou Hui-Yuan; Wang Chang-Shou   

  1. Department of Modern Physics, Lanzhou University, Lanzhou , People's Republic of China 730000
  • Received:1992-01-22 Revised:1992-07-31 Published:1993-08-15
  • Contact: Tao Zu-Yi

Abstract: The intrinsic protonation constants of three steps of chelating ion exchange resin D751 containing iminodiacetic groups in water and ethanol-water mixtures have been deter-mined at 25 ℃ by potentoimetric titration and by means of the extrapolation procedure without the assumption on the activity coefficients of charged species in the resin phase. The changes in the acid-base properties of the chelating resin D751 in the water and the ethanol-water mixtures have been obse-rved, and the observed effects are explained. The variation of apparent protonation constants with the degree of neutralizaton has been demonstrated.

Key words: Chelating ion exchange resin, Apparent protonation constant, Intrinsic protonation conatant, Ethanol-water mixture solvent