CONICET | Buscador de Institutos y Recursos Humanos

Mechanical treatments of clay minerals are of great interest because produce materials of great specific surface area that can be used as adsorbents of different contaminants. In addition to the grinding, ultrsound is a technique recently used for the reduction of the particle size and enhanced surface. Diuron is anherbicide widely used in agriclture. It has been often found as an emerging pollutant in soils and water. The aim of this work was to study the effect of mechanical treatments (grinding and ultrasound) in the adsorption of diuron on montmorillonite from Rio Negro province, Argentine and sepiolite from spain. The samples were gound in amil for 30 to 80s. the raw materials in aqueous suspention underwent an ultrasonic treatment, using Misonix liquid procesor of 600W for 1 h. The samples were characterized by XRD, SEM, IEP and specific surface area. A variation of specific surface area was found (from 168 to 256 m2/g and 30.5 to 122 m2/g, for montmorillonite and sepiolite, respectively). The sonicated samples, were less affected in thir cristalinity than grinded samples. Adsorption of Diuron for unreated and treated samples was very similar. The adsorption isotherms of sepiolite showed values higher than those for montmorillonite, reaching a plateau at a value of 6.5 ìmol/g. The adsorption capacity of the different samples was correlated with their external surface. The sonicated sepiolite showed the higher adsorption capacity.