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Adsorption by activated carbon is a promising technique to remove tracepharmaceuticals (PhACs) and endocrine disrupting substances (EDS) during drinkingwater treatment. Two common granular activated carbons (GAC) (coal-based CalgonF400 and coconut-based PICACTIF TE (PICA)) were evaluated for the removal ofibuprofen, naproxen, carbamazepine, and nonylphenol (NP) in ultrapure water. The targetcompounds were chosen through a comprehensive evaluation including field study datafrom a river in Southern Ontario. Considering that environmental concentrations ofPhACs and EDS are usually 1g/L, isotherm tests were conducted at low initialconcentration (1000 ng/L) with equilibrium concentrations ranging from 10 - 800 ng/L.The authors are not aware of GAC isotherm data of PhACs and EDS at such low levels.A database of isotherms at low concentration level is of importance when selecting andevaluating appropriate GAC for water facilities. Unfortunately, ibuprofen isotherm datacould not be obtained due to unexplained losses in control samples during equilibration.The equilibrium data were analyzed by both linear and nonlinear regression methods inthe forms of Freundlich, Langmuir, and Langmuir-Freundlich (LF) equations. The lattermethod showed better isotherm data fit. Surprisingly, the adsorption capacity for bothcarbons was much lower for NP than that for naproxen and carbamazepine at lowconcentrations. Although the PICA showed a somewhat higher capacity than F400carbon, both would be able to effectively remove the three target compounds at testedconcentrations in ultrapure water. Although isotherm data in ultrapure water provides astarting point, further research should consider other factors influencing adsorption suchas competition and fouling from natural organic matter (NOM) in real water. Includes 19 references, tables, figures.

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Edition: Vol. - No. Published: 11/01/2005 Number of Pages: 16File Size: 1 file , 450 KB