Control of Emerging Contaminants by Granular Activated Carbon and the Impact of Natural Organic Matter

This research ranked the adsorbability of 115 emerging contaminants by granular activated carbon (GAC) from drinking water, mainly the organic chemicals identified on the Contaminant Candidate List 3 (CCL3), using classical and quantum quantitative structure activity relationships (QSAR). 80% of the investigated contaminants were classified as cost effectively treatable by GAC based on the models. A rapid small-scale column test (RSSCT) conducted with Lake Ontario water spiked with 8 selected emerging contaminants showed the modeling results were accurate. This research also tested the hypothesis that GAC exhaustion for geosmin and 2-methylisoborneol would be due entirely to natural organic matter, and would occur independently of the presence of these two compounds. RSSCT results confirmed this hypothesis. Mathematical modeling supported this observation by demonstrating that the ratio of the effluent concentration to the influent concentration of a trace organic contaminant is only dependent on the NOM loading state at any bed depth.MAS