Association of dodecylsulfate ions with ethylenediamine dihydrochloride

Abstract

The effect of sodium dodecylsulfate (SDS) on the acid-base properties of ethylenediamine (En) is studied at 308 K using potentiometric titration. Reduction of the acid function of EnH2 2+ cation (ΔpKmax ≃ 1.6) is found at the surfactant concentration Cs below the critical micellization concentration (CMC), while SDS micelles do not produce any additional effect. The effect found is accounted for by the formation of strong associates between the EnH2 2+ and DS-ions (logKas ≃ 6.5). © 1996 MANK Hayka/Interperiodica Publishing.