Abstrakt

Determination Of Point Of Zero Charge Of Tunisian Kaolinites By Potentiometric And Mass Titration Methods

A.Kriaa, N.Hamdi, E.Srasra

This paper deals with determining points of zero charge of natural and Na+- saturated mineral kaolinites using two methods: (1) acid-base potentiometric titration (2) mass titration. The two methods involved points of zero charge approximately similar for the two kaolinites between 6.5-7.8, comparable to those reported previously and were in the range expected for these clay minerals. The comparison of potentiometric surface titration curves obtained at 25ºC and those published in the literature reveals significant discrepancies both in the shape and in the pH of PZNPCs values.