GAC ADSORPTION OF INTERMITTENTLY LOADED PESTICIDES

The removal efficiency of intermittently applied pesticides by a granu lar activated carbon bed preloaded with background organic matter (BOM ) was examined using the rapid small-scale column test. Preloading wit h BOM decreased the removal efficiency of the pesticides. The removal efficiency was a function of the amount of BOM adsorbed, but was unrel ated to the influent concentration of the pesticide. A modeling approa ch employing the ideal adsorbed solution theory and a linear driving-f orce expression for intraparticle surface diffusion adequately simulat ed these phenomena.