Performance of Terbutryn Removal by Adsorption on HDTMA-Organoclay

Abstract

Pesticides are among the persistent organic pollutants (POPs) that are prohibited under Stockholm Convention. Frequently used to increase agricultural productivity, pesticides can be carried to surface water bodies or groundwater by surface runoff and infiltration. Being as a diffuse pollutant, it has become more important to remove pesticides in place by implementing in-situ solutions. Filtration trenches can be deployed to treat agricultural runoff while it flows through. One of the best material to be used as a component in such trenches could be clays with high adsorption capacities at low cost. However, the hydrophilic surfaces of clays cannot remove hydrophobic contaminants such as pesticides efficiently. Therefore, organoclays produced by intercalation of clay surfaces by surfactants are proposed to remove hydrophobic contaminants. For this study, organoclays are synthesized using beidellite clay and HDTMA surfactant. Adsorption kinetics of natural clay and organoclay are conducted to determine if organoclays enhanced removal of terbutryn and are appropriate to use in filtration trenches to treat pesticides.