Photocatalytic degradation of pesticides by titanium dioxide and titanium pillared purified clays

Titanium dioxide was synthesized by the sol-gel method and titanium pillared purified clay was prepared with two titanium contents: 1.15 and 10.5 mmol of Ti per gram of clay. The composites were synthesized by immobilizing TiO2 onto surfactant-pillared clay via ion exchange reaction between clay with cation surfactant, cetyl-trimethyl ammonium bromide (CTMABr). The composition and texture of the prepared photocatalysts were characterized with X-ray powder diffraction (XRD), FT-IR spectroscopy, transmission electron microscopy (TEM) and energydispersive spectroscopy (EDX). The adsorption performance and photocatalytic activities of the prepared samples were investigated using 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4-dichlorophenoxypropionic acid (2,4-DP) as models of organic pollutants. The results were obtained that these photocatalysts can effectively degrade selected pesticides. The removal efficiency increases with the Ti content in the pillared clay. (C) 2011 Production and hosting by Elsevier B.V. on behalf of King Saud University.