Measure of Zeta Potential of Titanium Pillared Clays

SOFÍA S. ZACUR VERCELLONE; EDGARDO SHAM; ELSA MÓNICA FARF.AN TORRES

Procedia Materials Science

Elsevier

Lugar: Amsterdan; Año: 2015 vol. 8 p. 599 - 607

The change of the zeta potential, ζ , with the pH as well as the isoelectric point of a charged particle are electrokinetic propertiesthat characterize it. The TiO2 pillared clays are very interesting materials because of their ability to adsorb polluting substancesand their potential to be used as photocatalyst in their degradation. That is why the preparation and characterization of thesematerials are important to improve their use in environmental chemistry. The aim of this work was the comprehension of theelectrokinetic behavior of TiO2 pillared clays by the determination of ζ and characterization of two TiO2 pillared clays and twoTiO2 pillared organoclays prepared using different acid of hydrolysis, as well as in the original clay. The pillared organoclayspresented a lower variation in the shape and the slope of the curves and in the IEP respect to that of the original clay. Thisbehavior is due to the fact that the pillared organoclays has a lower content of pillars than that of the TiO2 pillared clays, becausethe alkylamonium cation blocks part of the available exchanging sites for the anchored of the TiO2.xH2O species. When thesematerials are calcined the number of negative charged sites neutralized by TiO2 will be minor than that observed for the pillaredclays prepared in absence of surfactant. In consequence we can say that the preparation of TiO2 pillared clays usingalkylammonium allows to obtain materials with a controlled superficial charge and porosity that can favor the access of pollutingsubstances and their subsequent degradation in photatalytic treatments process.