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Research to-date has reported the presence of endocrine disrupting compounds (EDCs),pharmaceuticals and personal care products (PPCPs) usually at sub g/L concentrationsmostly in surface water and to a lesser degree in ground and drinking water (Richardson andTernes, 2005). Since limited knowledge is available on health effects related to theconsumption of drinking water containing trace amounts of EDCs/PPCPs, removal of thesecompounds during drinking water production is desirable. Pressure driven membraneprocesses such as nanofiltration (NF) and reverse osmosis (RO) may be promising techniquesfor the removal of these emerging micropollutants. Removal mechanisms of thesemicropollutants by nanofiltration include the perspective of interaction between the compoundand the membrane. The study distinguishes between three compound-membrane interactions; namelysize exclusion, electrostatic repulsion and adsorption. These interactions are determined bycompound properties (molecular weight/size, charge, hydrophobicity) and membraneproperties (MWCO (molecular weight cut-off)/pore size, surface charge, hydrophobicity).Operational problems such as fouling (decrease in membrane flux over time) has hamperedthe acceptance of RO and NF technologies (Kaiya et al., 1996). Membrane foulingcharacteristics were described as pore blockage, pore restriction and cake formation. Recentstudies (Xu et al. 2006 ; Plakas et al. 2006 ; Agenson et al. 2007) have reported that membranefouling can significantly affect the separation behavior of organic micropollutants, resultingin either an increase or decrease in retention as compared to a clean membrane. These studieshave focused on fouling caused by secondary effluents, humic substances and activated sludgeor landfill leachate. To our knowledge few, if any, studies have focused on the impact offouling by surface waters on the removal of micropollutants. The objective of this study was tosimultaneously evaluate the fouling potential and removal performance of thin film compositenanofiltration membranes. Experiments were conducted in ultrapure water and surface waterspiked with two pharmaceutical active compounds, namely naproxen and carbamazepine. Includes 7 references, table, figures.

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Edition: Vol. - No. Published: 11/01/2007 Number of Pages: 5File Size: 1 file , 300 KB