Abstract:

The effect of ionic strength on the exchange ratio E(%)-pH curves and isotherms of copper-illite system in NaClO4 and NaCl media have been studied. Two new phenomena were observed. One was the right-left shift of E(%)-pH curves with increasing ionic strength and the other was the down-up shift of isotherms with increasing ionic strength. Because of the complexation effect of Cl-, the exchange ratio of Cu in NaCl medium was lower than that of Cu in NaClO4 medium. The ionic strength might change the location of isotherms, but it didn’t change their L-F-4 type in isotherm classification. The results have been explained qualitatively and could be applied to ocean geochemistry and were of practical significance for protecting the ocean environment against pollution.

Key words: Ionic strength, Adsorption, Illite, Copper