Synthesis of polymeric microparticles for water purification

In the present study, highly crosslinked poly(styrene/meta-diisopropylbenzene) P(St/mDIB) microparticles were prepared employing both an emulsifier-free emulsion polymerization and a single-step swelling polymerization process. The effect of the crosslinker concentration on the particle size and morphology was examined experimentally. Polystyrene microparticles were also prepared by emulsion polymerization in the presence of beta-cyclodextrin, P(St/beta-CD). The ability of the synthesized polymeric microparticles to adsorb various organic pollutants (e.g., styrene, trihalomethanes and chlorinated volatile organic compounds) from aqueous solutions was examined by gas chromatography (GC). It was shown that the particles exhibit a moderate affinity for styrene, a low affinity for trihalomethanes and a high affinity for volatile organic compounds (VOCs), higher than that of activated carbon (AC). The polymeric microparticles were subsequently impregnated into ceramic, SiC/TiO2 and Al2O3, filters. The hybrid filters were used for the purification of potable water and their adsorption capacity was examined by high performance liquid chromatography (HPLC). It was shown that a SiC/TiO2 filter, impregnated with P(St/mDIB) microparticles, exhibits increased adsorption efficiency as compared to the empty ceramic filter. (c) 2007 Elsevier Inc. All rights reserved.