Measure of Zeta Potential of Titanium Pillared Clays

ZACUR VERCELLONE, SOFÍA SUSANA; SHAM, EDGARDO LING; FARFÁN TORRES, ELSA MÓNICA

Procedia Materials Science

ELSEVIER

Año: 2015 vol. 8 p. 599 - 607

2211-8128

The change of the zeta potential, ζ, with the pH as well as the isoelectric point of a charged particle areelectrokinetic properties that characterize it. The TiO2 pillaredclays are very interesting materials because of their ability to adsorbpolluting substances and their potential to be used as photocatalyst in theirdegradation. That is why the preparation and characterization of thesematerials are important to improve their use in environmental chemistry. Theaim of this work was the comprehension of the electrokinetic behavior of TiO2pillared clays by the determination of ζ and characterization of two TiO2 pillaredclays and two TiO2 pillared organoclays prepared using differentacid of hydrolysis, as well as in the original clay. The pillared organoclays presenteda lower variation in the shape and the slope of the curves and in the IEPrespect to that of the original clay. This behavior is due to the fact that thepillared organoclays has a lower content of pillars than that of the TiO2pillared clays, because the alkylamonium cation blocks part of the available exchangingsites for the anchored of the TiO2.xH2O species. Whenthese materials are calcined the number of negative charged sites neutralizedby TiO2 will be minor than that observed for the pillared claysprepared in absence of surfactant. In consequence we can say that thepreparation of TiO2 pillared clays using alkylammonium allows toobtain materials with a controlled superficial charge and porosity that canfavor the access of polluting substances and their subsequent degradation inphotatalytic treatments process.