Modeling the adsorption of emerging contaminants on activated carbon: classical and quantum QSAR approaches

The adsorption of 115 emerging contaminants, mainly organic chemicals identified by the US Environmental Protection Agency's 2009 Contaminant Candidate List 3, was ranked using two published classical quantitative structure-activity relationship (QSAR) models and a newly developed quantum QSAR model. Approximately 75% of the investigated contaminants were predicted to be cost-effectively treatable, with an activated carbon usage rate below 10 mg/L. A limited experimental validation campaign was carried out by rapid small-scale column testing (RSSCT) using Lake Ontario water for eight selected compounds: 17β-estradiol, ibuprofen, diazinon, sulfamethoxazole, carbamazepine, 4-nonylphenol diethoxalyate, azithromycin and tylosin, with the activated carbon adsorption of the latter three having never been previously reported. The experimental results were consistent with the quantum chemistry model rankings.