Adsorption of atrazine from aqueous solution on heat treated kerolites

The adsorption of 6-chloro-N-2-ethyl-N-4-isopropyl-1,3,5-triazine-2,4-diamine (atrazine) on heat treated kerolite samples at 110 degreesC (K-110), 200 degreesC (K-200), 400 degreesC (K-400) and 600 degreesC (K-600) from aqueous solution at 25 degreesC has been studied. The evolution of surface properties of kerolite samples such as specific surface area and porosity after heat treatment was analysed. The clays were characterised by using usual techniques: FTIR spectroscopy, XRD diffraction, TG and DTG analysis, surface analysis and Hg porosimetry. The adsorption experimental data points have been fitted to the Freundlich equation in order to calculate the adsorption capacities (K-f) of the samples; K-f values range from 468 mg kg(-1) for the K-110 sample up to 2291 mg kg(-1) for the K-600 sample. The values obtained for the removal efficiency (R), (percentage of pesticide removed), ranged from 48% for K-110 up to 78% for K-600. The adsorption experiments showed that the stronger heat treatment, the most effective adsorption of atrazine, so, as this type of clay is relatively plentiful, these activated samples might be used in order to remove this pesticide from water. (C) 2003 Elsevier Science Ltd. All rights reserved.