IMPACT OF ORGANIC-MATTER ADSORBABILITY ON MICROPOLLUTANT REMOVAL BY ACTIVATED CARBON

Background organic matter (BOM) is well known to have a major influenc e on the removal of micropollutants such as pesticides for decreasing the efficiency of activated carbon in a drinking-water treatment facil ity. Numerous studies have described the influence of BOM-concentratio n on micropollutant removal. In this study, however, the influence of the adsorbability of BOM on the adsorption behaviour of the micropollu tant was examined. In laboratory scale tests, water samples were pre-t reated with a specific procedure to obtain equivalent BOM concentratio ns and different BOM adsorbability. These pre-treated samples, spiked with atrazine as a micropollutant, were used for isotherm measurements . Decreasing adsorbability of BOM yields a higher effectiveness of the activated carbon to remove atrazine. A prediction of atrazine breakth rough curves for a granular activated carbon filter suggested a practi cal relevance. The removal of atrazine out of a water containing weakl y adsorbing BOM should be much more effective in comparison with a tre atment of a water with well adsorbing BOM.