An investigation on the application of CaII-FeII-FeIII magnetic hydrotalcite-likecompounds for the removal of impurities in aqueous systems

Abstract

The main aim of this study is to investigate the feasibility of utilizing novel hydrotalcite-like-compounds as ionexchangers for the removal of anionic impurities from aqueous solution. Hydrotalcite is naturally occurring, rarelyfound anionic clay. It has a positively charged layered structure consisting of two metal oxide layers and an interlayerof carbonate anions. Hydrotalcites can, therefore, be used as ion-exchangers. However, the carbonate anion is highlyselected by natural hydrotalcite, making the ion-exchange capacity for other anions very low. In this study, severalsynthetic hydrotalcite-like compounds and a magnetic hydrotalcite-like compound samples were prepared in order toremove anionic impurities from waters. The physical structure and chemical properties of these anionic clays werecharacterized using standard characterisation techniques. The removal capacities of the synthetic products obtainedwere then investigated. Magnetic hydrotalcite-like-compound, namely, CaII-FeII-FeIII, was proved to be a good ionexchanger.