Removal of 17β-oestradiol and 17α-ethinyl oestradiol from water by activated carbons and hypercrosslinked polymeric phases

There has been growing concern about man-made and naturally occurring chemicals in the environment in recent years. These chemicals interfere with the hormone (or endocrine) system, suggesting far-reaching effects on reproduction and development in current and future man and wildlife generations. Recent research has highlighted the existence of these substances in sewage and industrial effluents and their potential for recycling back into the environment, including drinking water, through point and non-point sources. 17 beta-Oestradiol (E2) and 17 alpha-ethinyl oestradiol (EE2) are amongst the compounds of concern since they were found to cause adverse effects to fish even at low concentration levels. In this work, the adsorption of E2 and EE2 onto several granular activated carbons and Macronet polymers was investigated by batch experiments after a low level detection system was developed using Gas Chromatography Mass Spectrometry (GC/MS). Equilibrium experiments were carried out for all adsorbents to quantify the sorption capacity for E2 and EE2 and the data were correlated using conventional theoretical treatments. For better assessment of the sorbents, their physical properties including surface area, average pore diameter and micropore volume and chemical structure were characterised by N-2 adsorption experiments. Further characterisation was performed with scanning electron microscopy (SEM), FTIR spectroscopy, sodium capacity determination, pH titration, development of proton-binding curves and zeta potential measurements. Kinetic experiments were performed at different size ranges of adsorbents and the results were analysed by applying a particle diffusion model. This study demonstrates the potential of these adsorbents for the removal of endocrine-disrupting compounds from aqueous solution. (C) 2010 Elsevier Ltd. All rights reserved.