Magnetic nanoparticle adsorbents for emerging organic contaminants

The recognition that pharmaceuticals, personal care product chemicals, and endocrine disruptors can cause deleterious effects has led to search new approaches for removing them from contaminated waters. The emergence of tailored nanomaterials, with magnetic properties and high adsorption capacity for a wide range of compounds, provides a new tool to deal with these complex emerging organic contaminants (EOCs). Magnetic permanently confined micelle arrays (Mag-PCMAs) synthesized with cationic surfactants can provide several sorption mechanisms for the multifunctional EOCs. The sorption onto Mag-PCMAs of seven EOCs and two more conventional contaminants was studied. The results indicate high sorption capacity for many of the EOCs. However, because of the complex nature of these EOCs, it is not possible to predict their adsorption based on a single physicochemical characteristic such as Kow or pKa. Sorption kinetics are relatively fast, within the typical range for water treatment processes. The low energy required for the synthesis of Mag-PCMAs, relatively low cost (∼$4/kg), ease of recovery with a magnetic field, and regenerability make them a much more sustainable option than more traditional approaches for removing EOCs, such as high energy granular activated carbon adsorption or advanced oxidation processes. © 2013 American Chemical Society