Adsorption of metallic ions on maize stalk before and after thermal treatment

Nowadays, most industries produce significant quantities of wastewater, which, before discharge into surface waters or sewerage networks of municipalities, must comply with the limits imposed by current legislation, including metals. A number of conventional technologies may be involved to eliminate metals from wastewater,
including chemical precipitation, ion exchange, membrane separation and adsorption using various materials. These methods are sometimes not so efficient when the concentration of metals in aqueous medium is low. In addition, large amounts of generated waste require treatment and storage. On the other hand, is expensive to treat large volumes of water where metals are found in low concentrations. In recent years, biosorption using various natural materials has emerged as an ecological alternative for keeping metallic ions at low concentrations. Moreover, this approach is environmentally eco-friendly and the materials used are cheap and available in abundance. Also, bio sorbents can retain metals selectively and efficiently. In our study, the adsorption characteristics of maize stalk before and after thermal treatment were tested for removal of Cu(II), Pb(II), Cr(III) and Fe(III) ions from synthetic solutions.